PSYCHOLOGY, PSYCHIATRY & BRAIN NEUROSCIENCE SECTION

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1 Pain Medicine 2015; 16: Wiley Periodicals, Inc. PSYCHOLOGY, PSYCHIATRY & BRAIN NEUROSCIENCE SECTION Original Research Articles Living Well with Pain: Development and Preliminary Evaluation of the Valued Living Scale Mark P. Jensen, PhD,* Kevin E. Vowles, PhD, Linea E. Johnson, BA,* and Kevin J. Gertz, MPA* *Department of Rehabilitation Medicine, University of Washington, Seattle, Washington; Department of Psychology, University of New Mexico, Albuquerque, New Mexico, USA Reprint requests to: Mark P. Jensen, PhD, Department of Rehabilitation Medicine, University of Washington, Box , Harborview Medical Center, 325 Ninth Avenue, Seattle, WA 98104, USA. Tel: ; Fax: ; Conflict of interest: The authors declare no financial or other relationships that might lead to a conflict of interest related to this study. Funding sources: None declared. Author contributions: All authors reviewed and provided comments on drafts and subsequent revisions of this article, and approved the final version for submission and publication. MPJ and KEV wrote the original item pool of the VLS items. MPJ participated in the design of the primary study, provided input into the design of the analysis plan, and prepared the first draft of Introduction, Methods, and Discussion. KEV conducted the statistical analyses and prepared the first draft of Results section. LEJ collected the study data under KJG s supervision, and KJG participated in the design of the primary study and supervised data collection and data management. Abstract Objectives. Encouraging individuals with chronic pain to focus on nonpain-related goals that are consistent with personal values is a goal of most psychosocial pain interventions. A valid and reliable measure of goal-related variables would be useful to evaluate the importance of these to patient quality of life and as factors that may explain treatment outcome. Design. We developed items for a measure (the Valued Living Scale, VLS) to assess goal importance, success, and confidence with respect to eight value domains and 26 specific values-related goals, and administered these items to individuals with three chronic pain conditions (low back pain, N 5 58; fibromyalgia, N 5 55; headache, N 5 61). Results. Analyses supported: 1) a two-factor model of the VLS items assessing goal-related variables associated with a) health and productivity and b) social relations; 2) VLS scale score reliability, with Cronbach s alphas greater than 0.70; and 3) VLS scale score validity, as indicated by significant associations with pain intensity, depression, and pain interference in the expected directions. Conclusions. The VLS items can be administered and scored to assess: 1) the importance of as well as 2) confidence in and 3) success in achieving values-consistent goals. The measure can be used by clinicians to monitor and track changes in patient s perceptions about their goals with treatment. Researchers can use the VLS to test theoretical models of the roles that patient perceptions about goal importance, confidence, and success play in chronic pain treatment outcome. Summary This study described the development and preliminary validation of a measure that assesses: 1) the importance of as well as 2) confidence in and 3) success in achieving valued life goals. The measure may be used to monitor and track changes in patient perceptions of their goals during treatment, 2109

2 Jensen et al. and researchers may use the measure to test the role that patient perceptions about goal importance, confidence, and success play in chronic pain treatment outcome. Key Words. Assessment; Chronic Pain; Psychology; Self-Efficacy; Values Introduction Chronic pain can have a profound negative impact on functioning [1 3]. Although psychosocial pain treatments have been shown to result in some reductions in pain intensity, these treatments tend to focus on improvements in physical and psychological functioning as primary targets [4 8]. One of the mechanisms by which improvements are hypothesized to occur is via a shift in patient focus away from a primary goal of pain reduction toward goals associated with living meaningful and productive lives [5,6,8,9]. Research is consistent with this idea. For example, measures of perceived success in living according to one s values assessed by the Chronic Pain Values Inventory (CPVI) [10] and the Valued Living Questionnaire (VLQ) [11] have been shown to be associated with measures of both psychological and physical functioning [10,12,13]. Moreover, the assessment of values in individuals with chronic pain is consistent with a number of therapeutic models, such as acceptance and commitment therapy (ACT), Contextual Cognitive Behavioral Therapy, and Motivational Interviewing approaches to pain treatment [8 10,14]. However, the existing measures of valued living are missing items that are needed to determine the role that some values-consistent goal factors may play in treatment outcome. Specifically, there are no measures that assess: 1) perceived ability to attain goals (i.e., confidence or self-efficacy [15]) or 2) specific goals as opposed to general goal domains (e.g., maintaining an appropriate exercise regimen as opposed to maintaining health). Self-efficacy is a central construct of Social Cognitive Theory [16] and other Expectancy-Value models [17]. In addition, self-efficacy is hypothesized to be a key mechanism of the beneficial effects of Motivational Interviewing [9,18], which is a psychosocial treatment being increasingly applied to chronic pain problems [9,19 21]. While pain-related self-efficacy measures exist [22 24], crucially they do not assess self-efficacy regarding values or value-related domains. Thus, a measure assessing goal attainment confidence (i.e., selfefficacy for achieving a goal) would be useful for clinicians who want to monitor this factor, as well as for researchers who want to examine the role that selfefficacy may play in explaining treatment outcomes. The purpose of this study was to develop a comprehensive measure of patient perceptions about their valuesconsistent goals. We hoped that the resulting measure would: 1) have both brief and longer versions; 2) assess multiple goal domains, including specific goals; and 3) assess confidence regarding goal attainment in addition to overall goal importance and perceived success in goal attainment. We hypothesized that, if valid, the measure s score scales would be significantly associated with measures of depression and pain interference, even when controlling for pain intensity and demographic variables. We also hypothesized that if the scale scores from a brief version represented the scores computed from a longer version, they would be correlated very strongly (i.e., 0.80 or greater) with one another. Finally, we hypothesized that, when controlling for the brief scale scores, scores created from the longer versions would not contribute substantially or significantly to the prediction of the criterion variables. Methods Study Participants The study participants were recruited from a group of individuals who had participated in a study examining the words patients use to describe pain [25]. These individuals in turn had been recruited from pools of patients with three chronic pain diagnoses (low back pain, headache, fibromyalgia) who had received treatment at the University of Washington Medical Center. Of 302 patients from this pool who were approached to participate, 174 (58%) agreed to respond to the measures administered for this study. Inclusion criteria for both studies included: 1) being able to speak English; 2) being at least 18 years of age; 3) having a diagnosis of low back pain, fibromyalgia, or headache as per hospital records; 4) reporting the presence of bothersome pain associated with their diagnosis in the past three months; and 5) reporting a worst pain intensity rating in the previous week of 3 or more on a 0 10 numeric rating scale (NRS). Although a pain intensity level of 3 (out of 10) falls into the mild range of intensity that has been shown to have minimal impact on functioning [26,27], the inclusion of individuals with relatively low levels of pain intensity in this study helped to ensure an adequate level of variability in pain intensity scores for the planned analyses (described below) that used pain intensity as a criterion or predictor variable. Participants were not paid for completing the interview. The study procedures were approved by the University of Washington Institutional Review Board. Procedures and Measures After answering questions related to the first study (assessing demographic variables and how participants describe their pain [25]) during a telephone interview, and agreeing to continue with the interview, the participants in this study were asked to respond to questions assessing: 1) depressive symptoms, 2) pain interference, 3) pain intensity, 4) relationship style, 5) the importance, confidence, and success in achieving 34 goals that fell into eight value domains (these questions made up the item pool for the measure to be developed and 2110

3 Valued Living Scale validated, titled the Valued Living Scale or VLS), and 6) the extent to which they believed they need to feel better to achieve their goals. 1 By assessing the importance of each goal, the VLS items allow for an identification of the specific goals that are most valued by each respondent. The overall importance (or value) of a goal is hypothesized to be a key factor that determines which goal(s) will play the most important role in guiding behavior by Expectancy X Value models [17,28], including Social Cognitive Theory [16]. These models argue that human behavior is driven primarily by the combined influence of both 1) an individual s perceptions regarding the likely outcomes of the behavior in question (expectancy) and 2) the overall importance of those outcomes to the individual (values). These models argue that people will engage more in those behaviors that they believe they are capable of doing and that will result in valued outcomes than in behaviors that they do not believe they can do or that will not yield positive results. Thus, the assessment of self-efficacy in goal attainment allows for an assessment of the first of these two key factors. Finally, by assessing success in goal attainment, the responses make it possible to compute discrepancy scores reflecting the extent to which the respondent perceives that he or she is living a life more (or less) consistent with the values-consistent goals that are most important to him or her. Responses to the questions assessing depression, pain interference, and pain intensity, and the VLS item pool items were used to address the aims of this study. Depression symptoms were assessed using the 20- item Center for Epidemiological Studies-Depression Scale (CES-D [29]). The CES-D was developed as a measure of depressive symptoms for studies in individuals in the general population, and asks respondents to indicate the frequency with which they have experienced 20 different depressive symptoms (e.g., depressive thoughts, dysphoric mood, vegetative signs) during the past week on 4-point Likert scales [from 0 5 Rarely or none of the time (less than 1 day) to 3 5 Most or all of the time (5 7 days) ]. The measure evidenced good internal consistency (Cronbach s alpha ) in the scale development sample. Internal consistency in the current sample (Cronbach s alpha ) replicated this score. Pain interference was assessed using the 20-item Pain Disability Assessment Scale (PDAS [30]). The PDAS assesses pain interference in three domains (interference with physical activities, activities of daily living, and social activities). The PDAS was developed in a sample of individuals with mixed chronic pain problems, and was selected for use in the current study because of its greater content validity relative to other existing measures of pain interference. The PDAS scores have evidenced high levels of test-retest stability (ranging from 0.86 to 0.96 over a 1- to 7-day period) and internal consistency (Cronbach s alphas ranging from 0.87 to 0.95) in the original scale development sample [30]. We used the PDAS total scale score (which showed an excellent internal consistency Cronbach s alpha in the current sample) in the current analyses. Two of the authors (MPJ and KEV) wrote 102 items to assess the importance, confidence, and success (during the past week) in achieving eight general domains (keeping healthy, feeling good, being a good parent, being a spiritual person, being a good spouse/partner, being a good friend, being productive, and being a good community citizen) and 26 specific goals that were associated with each of the eight primary goal domains. We called the measure the VLS. The domains were selected based on our consideration of the goal domains from existing measures [10,11], as well as our combined clinical experience of 45 years working in the field of chronic pain. Importance, success, and confidence for each of the eight general goal domains (e.g., keeping healthy ) and the 26 specific goals (e.g., eating the right amounts of health food ) was assessed using 0 10 NRS. The endpoints for importance, success, and confidence were as follows, respectively: 0 indicated Not at all important to me, Not at all successful at achieving or maintaining the goal, and Not at all confident I can achieve the goal ; 10 indicated Extremely important, Extremely successful, and Extremely confident. We planned to examine several scale scores, including scores for the general goal domains and specific goal items. The scale scores assessed importance of, confidence in, and success in achieving the 34 goal items. In addition, we planned to score the responses to yield two additional VLS scale scores that would take into account the level of confidence and success by the importance of each goal item; these scores were created by computing importance-confidence and importance-success difference scores, consistent with how such items are created by other scales [e.g., [10,11]. Data Analyses We computed descriptive statistics of the demographic variables to describe the study sample. We then performed a series of item analyses to: 1) select the specific items that would be included in the final measure and 2) determine which combination(s) of items resulted in psychometrically sound subscales. To accomplish these aims, we planned to eliminate any items that demonstrated an extremely skewed distribution (i.e., 90% or more responses at the extreme ends of the scale, 0 or 10; skewness 3.0). Next, we performed two exploratory factor analyses (EFAs), one for the items assessing success and the other for items assessing confidence, on the eight general domain items. We utilized the resultant factor structure to then guide confirmatory factor analyses (CFAs) of the 26 specific goal items. Because we expected items and the factors resulting from the factor analyses to correlate with one another, we used an oblique rotation (Geomin) method for rotating the factors. 2111

4 Jensen et al. Determination of the resulting factor structure was based on a number of considerations including scree plots, Eigenvalues, parsimony, interpretability, model fit, and comparative fit of different factor structures. With regard to the latter two indicators, the primary fit statistic used was the Root Mean Square Error of Approximation (RMSEA). For the RMSEA, values closer to zero indicate closer fit of the data with the model. Hu and Bentler [31] suggest a value of lower than 0.06 for good fit, while MacCallum et al. [32] have suggested cut-points of 0.01 for excellent fit, 0.05 for good fit, and 0.08 for modest fit. In addition, a 90% CI was calculated for the RMSEA to test for close model fit where a significant value indicates model fit was worse than close [33]. Finally, we assessed model fit using both an absolute fit index, the standardized root mean squared residual (SRMR), and incremental fit index, the Tucker Lewis Index (TLI). For the SRMR, values of 0.08 or below indicate acceptable fit, while TLI values at or above 0.95 indicate acceptable fit [31]. The EFA and CFA analyses utilized the Mplus version 7.11 software package [34], which also allowed us to examine the comparative fit of various factor solutions for the initial EFA analyses. After an initial factor structure was identified, we inspected item loadings and item-total correlations, as well as the internal consistency coefficients of the resulting scales. If these analyses indicated any problematic items, the problematic items were removed and the analyses repeated until a stable and psychometrically sound factor structure was identified for both the general and specific items. While missing data were rare, the nature of some of the questions allowed respondents to opt out for items that were not applicable (i.e., items asking about values and goals regarding being a parent and being a spouse or partner). We therefore used Maximum Likelihood (ML) estimation across all analyses. This method of estimation allows the use of all available data and is generally deemed appropriate for analyses that involve many variables and multistep analytic approaches. Furthermore, ML has been shown to minimize bias (in comparison to other methods of addressing missing data, such as mean substitution), achieve consistent estimates across analyses, and provide robust estimates of standard errors [35,36]. After the items for the VLS factor subscales were identified using the results of the factor analyses, we computed subscale scores representing importance, confidence, and success by simply averaging the responses to the items that loaded on each factor. Scores representing the average of the importanceconfidence and importance-success difference scores were similarly computed for each goal factor. We then performed a series of correlation and regression analyses to evaluate the relative validity of the subscales. In the regression analyses, we computed the amount of variance accounted for by the scale scores in predicting the two criterion validity variables (assessing depressive symptoms and pain interference) after controlling for patient demographic variables (i.e., gender, age, and pain duration) and pain intensity. Given the possibility that some of the derived scores and subscales would significantly overlap with one another, we anticipated that if any of the measure s scale scores were found to be associated significantly with the validity criterion, the other scores might not contribute independent variance; for example, success scores may not account for significant variance after confidence scores are controlled and vice versa, and the specific goal scales might not account for significant variance after the general goal scale is controlled. However, we thought it necessary to confirm this assumption empirically, and also identify which of these value domains demonstrated the strongest and most consistent associations with the validity criterion. If valid, we anticipated that measures of perceived goal attainment success and goal attainment efficacy would evidence negative associations with the criterion variables (i.e., more perceived success and self-efficacy associated with less depressive symptoms and pain interference), and that the importance-success and importance-self-efficacy difference scores would evidence the opposite pattern. We planned to select as final scales those scales that emerged from the factor analyses and that 1) demonstrated at least adequate reliability (as indicated by Cronbach s alphas of 0.70 or greater) and 2) demonstrated significant associations with the criterion variables in expected directions. Results Participant Description Most (n 5 144, 83%) of the participants were women, although the sex distribution within each diagnostic group varied to some degree: low back pain, n 5 40 (69%) women and n 5 18 (31%) men; fibromyalgia, n 5 54 (98%) women, n 5 1 (2%) men; headache, n 5 50 (82%) women, n 5 11 (18%) men. Average age was years (SD ; range ), with significant between group differences [F(2, 171) , P < 0.001; low back pain, years (SD ); fibromyalgia, years (SD ), headache, (SD )]. The majority of participants were also White (n 5 152, 87%), with the remainder describing themselves as Asian (n 5 6, 3%), Black (n 5 4, 2%), Native American (n 5 1, 1%), other race (n 5 1, 1%), or more than one racial group (n 5 10, 6%). Average pain (in the past week) was rated as 4.9 on a 0 10 NRS for the group as a whole, with no significant differences in average pain intensity among the three diagnostic groups, F(2, 173) 5 1.6, P Descriptively, pain intensity averaged 4.8 (SD 5 2.0) for the low back pain group, 5.3 (SD 5 1.8) for the fibromyalgia group, and 4.7 (SD 5 1.9) for the headache group. Initial Item Analysis For the majority of items, missing data were rare, with less than six responses missing for any single item 2112

5 Valued Living Scale Table 1 Factor loadings for ratings of success and confidence for general domain items Success Confidence General Domain Health and Productivity Social and Relational Health and Productivity Social and Relational Keeping healthy Feeling good Productivity Parenting Spirituality Spousal/partner relat Friendship Community/citizenship Note: N Primary factor loadings in bold. (<4%). The only exceptions were for the domains assessing goals related to parenthood (for which of responses were missing for any single item; 36 38%), spouse/partner relations (for which responses were missing for any single item; 40 41%), and spirituality (for which responses were missing for any single item; 6 13%). With regard to response frequencies, no item had more than 90% of responses at the extreme ends of possible scores, although some of the importance items approached this value (e.g., 89% rated Importance of becoming or maintaining as a nonsmoker as extremely important ). This tendency to rate most items as very important was also apparent when evaluating kurtosis, as the majority of the importance items (27 of 34; 79%) had evidence of significant kurtosis. This finding was not unexpected given that previous work demonstrated a similar finding when assessing the importance of valued areas [10]. Furthermore, previous work has also indicated the utility of the importance score in calculating the difference between values success and importance [e.g., [37,38]. Therefore, we decided to retain the importance items for use in calculating differences scores, but not to use them to create any independent subscales on their own. There were also four success/confidence items that were markedly kurtotic and, therefore, excluded from the factor analyses. The first two were specific goals from the general health domain and included both the success and confidence items for becoming or maintaining 1) as a nonsmoker and 2) as a light or nondrinker. The other two items were specific goals from the general parenting domain and included 1) maintaining/expressing affection and 2) giving emotional support to the child/children. That is, almost all of the participants reported a very high degree of both success and confidence in being a nonsmoker, a light or nondrinker, maintaining/expressing affection to their child/children, and giving emotional support to their child/children. We, therefore, eliminated these four items from the measure. Factor Analyses As noted, items from the eight general domains of keeping healthy, feeling good, parenting, spirituality, spousal/partner relations, friendship, productivity, and community citizenship were used initially to explore possible factor structure. Both the success and confidence items were used separately in EFA. Results of the EFAs were highly consistent across the two sets of items. Within both item sets, there was a lack of convergence for models including four or more factors; therefore, evaluation investigated the utility of a factor structure composed of one, two, or three factors. Overall, a two-factor model appeared appropriate and superior to alternate factor structures. The three-factor model for both sets of items was not interpretable as a single item (spirituality) had a negative estimated residual variance, which indicates the presence of either a single item factor or a factor within which a single item is accounting for the preponderance of the variance [35]. With regard to the selection of a one- or two-factor model, a comparison of model fit indicated improved fit for the two-factor model in relation to a single factor model for both sets of items (Success: v , P 5 <0.001; Confidence: v , P 5 <0.001). With regard to the two-factor model, an identical factor structure was indicated for both sets of items. The first factor was composed of the keeping healthy, feeling good, and productivity items and the second composed of the parenting, spirituality, spousal/partner relations, friendship, and community citizenship items. Model fit indices indicated a good fit within each EFA (Success items: RMSEA ; 90% CI: ; P close fit ; SRMR ; TLI ; Confidence items: RMSEA ; 90% CI: ; P close fit ; SRMR ; TLI ). Factor interpretation was straightforward. The first factor was labeled as Health and Productivity and the second as Social and Relational. Factor loadings are displayed in Table 1, overall, all primary loadings were in excess of 0.45 and 2113

6 Jensen et al. Table 2 Descriptive information for self-report measures Measure Mean (SD) Usual pain intensity (past week) 4.9 (1.9) Depression 21.7 (14.5) Pain Interference 24.7 (14.5) VLS General Goal Domains Health and Productivity Social and Relational Importance 9.3 (0.9) 8.8 (1.3) Success 6.3 (2.3) 7.5 (1.8) Confidence 5.9 (2.4) 7.0 (2.1) Importance-success 3.0 (2.2) 1.4 (1.9) Importance-confidence 3.4 (2.4) 1.8 (2.2) VLS Specific Goal Domains Importance 8.9 (0.9) 8.5 (1.3) Success 6.5 (1.9) 7.7 (1.7) Confidence 5.9 (2.1) 7.0 (2.0) Importance-success 2.4 (1.8) 0.8 (1.7) Importance-confidence 3.0 (2.1) 1.5 (2.1) Note: N all secondary loadings were less than Cronbach s alpha for all scales ranged from 0.75 (factor 2 confidence) to 0.82 (factor 1 success and confidence). With regard to the 22 specific goal items included in the analyses, CFAs using the factor structure identified in the general domain items provided a good fit with the data. For the success items, fit indices for a two factor model were RMSEA ; 90% CI: ; P close fit ; SRMR ; TLI Fit for a two-factor model of the confidence items were RMSEA ; 90% CI: ; P close fit ; SRMR ; TLI For the Health and Productivity factor, loadings ranged from 0.52 to 0.75 for the success items and 0.47 to 0.78 for the confidence items. For the social and relational factor, loadings ranged from 0.43 to 0.80 for the success items and 0.38 to 0.67 for the confidence items. Specific factor loadings are displayed in Supporting Information Tables S1 and S2 for the two factors, respectively. Cronbach s alpha for all scales ranged from 0.82 (factor 2 confidence) to 0.89 (factor 1 confidence). Correlation Analyses Descriptive information for all self-report measures including pain intensity, depression, pain interference, and the VLS scale scores are displayed in Table 2. All correlations are displayed in Supporting Information Table S3. The overall pattern of relations between the subscales for the success and confidence ratings, and both the validity criterion (depression, pain interference) and pain intensity was examined via Pearson Product Moment Correlations. As hypothesized, all scores were associated significantly with the measures of depressive symptoms (absolute r range , all P s < 0.001) and pain interference (absolute r range , all P s < 0.001). All subscale scores were also significantly associated with pain intensity (absolute r range , all P s < 0.05). For all correlations, relations were in the expected directions, with the success and confidence scores of the VLS showing negative associations with pain intensity, depression, and pain interference and the difference scores showing positive associations with these criterion variables. With regard to the VLS subscales, correlations across the subscales were generally moderate, suggesting concordance, but not complete overlap. Correlations between any two subscales ranged from 0.47 to 0.66 across the various scoring methods. Correlations were higher when the factor scores for the general and specific domains were inspected (e.g., factor 1 general goal domain score correlated with factor 1 specific goal domain score) and ranged from 0.77 to 0.84 all P < suggesting a high degree of concordance with regard to factor specific ratings, regardless of whether general or specific goal domains were assessed. Regression Analyses As the final step, we performed a series of regression analyses to evaluate how the measure s subscales related to key aspects of patient functioning, including depression, pain interference, and pain intensity. These analyses utilized scales created by averaging the measure items that loaded on the two factors identified in the EFAs. We scored four domains: overall success, the difference between importance and success, overall confidence, and the difference between importance and 2114

7 Valued Living Scale Table 3 Regression results for the general domain scores Depression Pain Interference Predictor Dr 2 b Dr 2 b Success 1. Gender 0.07**** 0.14* 0.04* Age 0.05*** 20.13* 3. Pain intensity 0.12**** 0.27**** 0.21**** 0.43**** 4. Success 0.24**** 0.09**** Health and productivity 20.41**** -0.32*** Social and relational 20.13* 0.01 Importance2Success 1. Gender 0.07**** * Age 0.05*** 20.18*** 3. Pain intensity 0.12**** 0.26**** 0.21**** 0.42**** 4. Importance success 0.20**** 0.07**** Health and productivity 0.37**** 0.19* Confidence 1. Gender 0.07**** 0.12* 0.04* Age 0.05*** Pain intensity 0.12**** 0.23**** 0.21**** 0.41**** 4. Confidence 0.27**** 0.08**** Health and productivity 20.43**** 20.27**** Social and relational 20.19** Importance2Confidence 1. Gender 0.07**** * Age 0.05*** 20.13* 3. Pain intensity 0.12**** 0.24**** 0.21**** 0.41**** 4. Importance confidence 0.23**** 0.06**** Health and productivity 0.38**** 0.16* Social and relational 0.19** 0.14 * P 0.05; ** P 0.01; *** P 0.005; **** P confidence. We performed eight regression analyses in all, two predicting the validity criterion (depression and pain interference) from the general success domain scale scores and two predicting the validity criterion from the general importance-success scale scores, followed by a set of four similar analyses using the confidence and importance-confidence difference scores as predictors. In addition to examining the individual utility of the subscale scores in accounting for variance in patient functioning, we sought to determine comparative utility across the four types of scores. Therefore, we performed two additional sets of regression analyses. The first evaluated whether the success and confidence scales appeared to be assessing independent aspects of patient functioning or whether there was evidence of significant overlap, which would indicate that the scales were essentially measuring the same construct. The second set of analyses evaluated whether the addition of the specific goal factor scales predicted unique variance in the criterion variables above and beyond the general domain scale scores. Within each regression, relevant demographic factors, including gender, age, and pain duration, were initially tested for entry in a stepwise fashion. We also controlled for pain intensity in the regression analyses predicting depression and pain interference. The VLS scores were entered next. Individual Scales As displayed in Table 3, both success and the importance-success difference scores accounted for significant variance above and beyond demographic measures and pain intensity (range r 2 D ). There was some variability in Beta-weights and significance levels between the Health and Productivity and Social and Relational activities scale scores, with Health and Productivity scores tending to show stronger associations with the criterion variables than the Social and Relational Activities scales. Moreover, the VLS scale scores evidenced stronger relations with depression than pain interference. Finally, the pattern of findings (i.e., negative associations between the criterion 2115

8 Jensen et al. variables and success, and positive associations between the criterion variables and importance-success difference scores) was consistent with the expected associations, assuming that the measures are valid. Table 3 also displays the confidence and the importance-confidence difference results. The pattern of results here was generally concordant with those found with the success scores. Significant variance was accounted for in each equation by the VLS scores after controlling for relevant demographic factors and pain intensity (range r 2 D ), the Health and Productivity scale scores tended to show stronger relations with the criterion than the Social and Relational scale scores, and the VLS scores evidenced stronger associations with depression than with pain interference. With regard to the specific goal scale scores, the pattern of findings was almost identical to that following the general domain scale scores. These results are displayed in Supporting Information Table S4. Significant variance was added by the specific goal factor scores across all equations (range r 2 D ) and significant beta-weights were indicated for the health and productivity factor in each case. The sole difference across analyses was that beta-weights for the Social and Relational scale were nonsignificant across all equations for the specific scale scores, whereas the general goal Social and Relational scale explained unique significant variance in depression across all domains. Comparison of Success and Confidence To examine the incremental utility of the success and confidence scores above and beyond one another, two sets of regressions were performed. The first set added the success scores after controlling for demographic variables and pain intensity, and then the confidence factor scores as the final step. The second set reversed the order of entry for the final two steps (i.e., confidence scale scores after the control variables and success as the final step). The results indicated that a modest, but significant, amount of additional variance was accounted for in all four analyses including depression (r 2 Dsrange, , all P s < 0.05). Across the analyses for pain interference, the additional predictor either success or confidence did not account for significant variance. Additive Value of Specific Goals after Controlling for General Domains Finally, the possible incremental utility of the specific goals scores above and beyond the general domain scores was evaluated. For these regressions, general domain scores were entered after controlling for demographic variables and pain intensity, and specific goals scores were entered in the final step. The overall pattern of results indicated modest value was gained by the addition of the specific goals and for the success and importance-success equations only, where the addition of the specific goal scores added a small amount of variance (r 2 D , P < 0.01 for both criterion variables). Discussion The results of this study indicate that the VLS items can be combined into related but distinct scales measuring importance, confidence, and success related to values-consistent goals for 1) health and productivity and 2) social and relational activity, and provide preliminary support for the reliability and validity of the VLS subscales. Reliability We planned to develop scales from the VLS items that evidence reliability coefficients (Cronbach s alphas) of at least 0.70, given that this is the standard minimum reliability required for a measure to be considered useful for research purposes [39]. All 20 possible scale scores [two goal clusters representing Health and Productivity and Social and Relational X two types of goal item stems representing general (8 stems) and specific (22 stems) goals X four value domains representing, confidence, success, importance-confidence, and importance-success] met this minimum criterion, and just over half (9 of 16, or 56%) had reliability coefficients that were 0.80 or greater. These findings indicate that the VLS scores are adequately reliable for research and clinical purposes. Construct Validity The domains assessed by the VLS and similar measures regarding values-consistent goals are hypothesized to play a central role in pain treatment outcome across different theoretical models of pain treatment [5,6,8,9]. Two other measures have been developed to assess some of the domains assessed by the VLS [10,11]. However, as mentioned in Introduction, each of these measures have limitations in the range or scope of what they assess (i.e., limited construct validity), which makes them less useful when clinicians or researchers need to assess more than just importance and success (i.e., wish to assess confidence), or need to assess importance, confidence, or success beliefs related to very specific goals. Given that almost all of the VLS item stems originally developed (30 of 34) were retained in the scale, its improvement in construct validity over existing measures was retained. Criterion Validity We hypothesized that if the VLS confidence, success, importance-confidence, and importance-success scale scores were valid, they would all correlate positively with measures of depressive symptoms and pain interference. This hypothesis was supported, with both the brief general domain and longer specific goal domain measures. The associations were particularly strong when predicting depressive symptoms. 2116

9 Valued Living Scale Whether these associations reflect a causal effect of depression on overall confidence and ability to succeed in goal attainment, an effect of confidence on goal success and therefore on depression, or mutual causation among these domains, cannot be determined based on the correlational analyses presented here. However, given the associations found, and given that both goal attainment confidence and success are the treatment targets of Motivational Interviewing [9,18] and operant treatment [6] approaches, respectively, it would be interesting to examine confidence and success as mechanism variables that could explain the effects of these treatments on depression in future studies. The achievement of increased success in valued areas is also a cornerstone mechanism hypothesized by ACT [40] and there is some support that improvements in perceived success in achieving valued goals, or minimizing the importance and success discrepancy, is an important factor in treatment success [37,41,42]. The VLS scales assessing four value domains (confidence, success, importance-confidence, importancesuccess) all accounted for about the same amount of variance in the validity criterion variables; none stood out as substantially more valid (as indicated by a substantially stronger validity coefficient) than the others. These findings indicate similar validity for the different VLS subscales. However, in the prediction of depressive symptoms, both success and confidence scales predicted significant (albeit a modest amount of) variance not accounted for by the other domain. This finding indicates that, although related, the success and confidence scales measure distinct domains, consistent with the idea they could potentially influence each other (i.e., having success in achieving a goal could increase subsequent confidence, and having confidence in achieving a goal could potentially influence subsequent success), but that success and confidence are not the same thing. Practically, these findings indicate that clinicians and researcher could use the VLS stems to assess either domain, as needed for clinical work or to address theoretical questions. The lack of substantial increases in the validity of the VLS using difference scores (i.e., taking into account the importance of each goal), relative to the absolute scores, warrants discussion. We found, as have others [11], that people generally view goals related to all of life domains as being very important that is, there appears to be relatively little variation in the importance of goals. As a result, the difference scores (or composite score if a product is used instead of a difference [11]) mostly reflect the success and confidence ratings. Indeed, we found that the associations between the scales based on difference scores were strongly associated with the scales based on absolute scores (see Supporting Information Table S3 for details), as have others when using similar procedures [10]. This raises the real possibility that it may not be necessary to ask for importance ratings or use these in computing scale scores. Eliminating these would reduce the assessment burden of the VLS (as well as similar scales, the CPVI [10] and the VLQ [11]), simplify the scoring procedures, and reduce the number of scales that would need to be included in analyses. Our only hesitancy in recommending that importance ratings be eliminated from the VLS and other similar measures at this point is that information regarding the importance of specific goals has clear clinical importance at the individual level, even when such information does not provide that much additional information at the group level. Knowing, for example, whether a specific health behavior (exercise) is more important to an individual than another health behavior (eating the right amounts of the correct foods) provides the clinician with information that is essential to the development of a treatment plan that takes into account patient preferences [9,18]. Thus, while we might suggest that researchers might consider dropping the importance ratings from the measure to reduce assessment burden in research studies, we are not advocating that these items be dropped from the VLS altogether. Similarly, the findings indicate that scales made up of both the brief (8 item stems) and longer (22 item stems) versions of the VLS are predictive of important criterion variables, and that the longer version of the VLS, while perhaps more useful in settings where clinical or research questions regarding very specific goals are of interest, is not needed to test hypotheses related to the role that goal importance, confidence, and/or success play in adjustment to chronic pain; the brief VLS appears adequately valid and reliable, and so would be useful in settings where assessment burden is an issue. There was one finding that was somewhat contrary to expectations. The second general goal domain (feeling good) included a number of items (e.g., decreasing or minimizing discomfort or pain ) that are hypothesized by ACT and operant models to have an inverse relation with effective functioning [6,8], particularly when pain control efforts displace other important values or pursuit of these values. The results of the EFA indicated that both the general domain and specific items assessing goal domains related to feeling good had strong and positive loading onto the health and productivity factor, which itself was negatively associated with depression and pain interference. Other findings, however, indicate that significant engagement in and prioritization of pain control efforts are associated with greater depression and pain interference (e.g., [43,44]), consistent with the operant and ACT models. There maybearolehereforamorefine-grainedanalysisof when and how pain control efforts might or might not contribute to further problems, or even might contribute to better functioning. For example,itmaybethata priority to decrease discomfortmayonlybeassociated with greater distress and pain interference when this goal displaces importance goals. Alternatively, such a priority may contribute to decreased success or confidenceinotherdomains,akey assumption within ACT for chronic pain [14]. 2117

10 Jensen et al. Study Limitations The sample was recruited from a pool of participants from a previous study who themselves were recruited from a large pool of patients seen at a university hospital. Thus, they represent a sample of individuals very willing to participate in research. Moreover, most of the sample were women (83%) and white (87%). Thus, the key findings, including the findings regarding the factor structure of the VLS items, will need to be replicated in other samples to evaluate their generalizability across chronic pain populations. In addition, because all of the data were collected via self-report, it is likely that at least some of the variance shared by the VLS scales and criterion variables could be due to shared method variance. Future research should examine the association between VLS scales and criterion variables assessed using more objective or alternative measures if possible, particularly given that the Social and Relational subscale was not consistently associated with Pain Interference. An additional limitation is that the original pool of VLS items were developed by two of the study investigators (MPJ and KEV) based on their combined clinical experience in working with individuals with chronic pain. Although the item generation was informed by the item authors significant (combined, over 45 years) clinical experience with individuals with chronic pain and the resulting measure is more comprehensive (i.e., content valid) than other existing measures assessing the same goal factors assessed by the VLS, it is possible even likely that there are goals important to individuals with chronic pain that are not assessed by the VLS items. In particular, although the original pool of items contained two specific goals related to being the kind of parent the respondent wants to be, only one of these items was retained in the final measure. Future research, including research using cognitive testing strategies in samples that include men and individuals from more diverse racial and ethnic backgrounds, should examine the content validity of the VLS items and determine if additional goal domains or specific goals are needed to improve the measure s content validity further. Given the cross-sectional design, we are also not able to make any conclusions regarding possible causal associations among the study variables. In addition, the sample size (N 5 144), while adequate for analyses involving the eight general goal items, is smaller than ideal given the number of specific goal items (22). Also, given the fact that statements about goals and values can be sensitive to social influence, it is possible that collecting data via telephone interview (instead of via paper-and-pencil item administration) might have influenced the responses in some unknown way. It would be useful to determine if the psychometric properties of a paper-and-pencil administered VLS are similar to those found here. It is also important to acknowledge that the VLS presented here is similar in a number of important ways to the two measures of goalrelated variables that have already been developed the VLQ and CPCI. The VLQ assesses the importance and value-consistency (success) of 10 general goal domains (e.g., family, relationships, work) [11], and the CPVI assesses the importance and perceived success in living according to one s values in 12 general goal domains (e.g., family, health, work) [10]. While the VLS differs from these other measures in that it 1) asks respondents to consider very specific goals (e.g., eating the right amounts of healthy food ) in addition to general goal domains and 2) assesses perceived confidence in goal attainment, there is still a great deal of overlap among these three measures. Future validity research should examine the associations among these measures, as well as their relative ability to account for variance in measures of important quality of life domains. Finally, although missing data were very rare for most items, these were more common for items related to parenting and spouse/partner relations, due to the fact that these items are not applicable if one is not a parent or is not married or in a significant relationship. This reduced the number of subjects available for analyses involving these items even more. Replication of the findings with additional and larger sample sizes would help establish their reliability. Conclusions Despite the study s limitations, the findings provide support for the validity of the VLS for assessing value dimensions related to both general and specific goals. The flexibility of the scale for assessing both general and specific value goals, as well as for assessing one or more of five different goal value domains (importance, confidence, success, importance-confidence, success-success), is a strength. Future research is needed to replicate the factor structure of the VLS item stems, as well as to evaluate the validity of the VLS scales in additional samples of individuals with chronic pain. If additional research confirms the reliability and validity of the VLS, its scales and items would likely be useful to clinicians to help identify goals to target in treatment, and by researchers to help evaluate the utility of a number of different clinical approaches and theoretical models that hypothesize a key role for goal-related values. Note 1. Responses to the first set of questions took about 15 minutes, and responses to the VLS questions took about 30 minutes. Participants were offered the opportunity to respond to the VLS items on another day if they were tired, but very few chose this option. References 1 IOM. Relieving Pain in America: A Blueprint for Transforming Prevention, Care, Education, and Research. Washignton, DC: The National Academics Press; Jensen M, Chodroff MJ, Dworkin RH. The impact of neuropathic pain on health-related quality of life: 2118