Subtypes of precontemplating smokers defined by different long-term plans to change their smoking behavior

HEALTH EDUCATION RESEARCH Vol.15 no.4 2000 Theory & Practice Pages 423 434 Subtypes of precontemplating smokers defined by different long-term plans to change their smoking behavior Arie Dijkstra and Hein De Vries 1 Abstract Although smoking tobacco is widely known to be potentially lethal, a large percentage of smokers still are not motivated to quit. For example, in the US the percentage of smokers with low motivation to quit smoking is about 40%, while in two European countries, the Netherlands and Spain, the percentages are even higher, 70 and 68%, respectively (Etter et al., 1997). According to the criterion, these smokers are not planning to quit within the next 6 months and are called precontemplators in the Stages of Change model (Prochaska et al., 1992). In attempts to lower the percentage of smokers in the population, interventions might be aimed at stimulating these precon- templators in the process of quitting. In the framework of the Stages of Change model, a stagematched intervention will have to be developed to target this group of smokers and to stimulate them to transit to the next stage, the contemplation stage. However, recent studies suggest that the large Many smokers are not motivated to quit smoking. In the Stages of Change model these smokers are called precontemplators. When developing interventions designed to motivate these smokers to quit, it is of importance to know whether this group is homogeneous or not. In the present study, different groups of precontemplators were distinguished according to their long-term quitting smoking plan: 861 precontemplators were asked to indicate the one plan that best fitted their own plans with regard to their smoking behavior: (1) planning to never quit and not planning to cut down (n 194), (2) planning to never quit but planning to cut down (n 186), (3) planning to quit somewhere in the future but not within the next 5 years (n 290), (4) planning to quit within the next 5 years (n 136) and (5) planning to quit within the next year but not within the next 6 months (n 54). These groups of smokers were compared on several variables cross-sectionally and longitudinally. The results indicate that the psychological factors that will have to be targeted in smoking cessation inter- ventions in efforts to motivate smokers to quit could be assessed reliably in precontemplators. Furthermore, precontemplators with different quitting plans differed on several cognitive Department of Clinical and Health Psychology, Leiden University, PO Box 9555, 2300 RB Leiden and 1 Department of Health Education, Maastricht University, PO Box 616, 6200 MD Maastricht, The Netherlands variables and the quitting plans at pre-test were predictive of quitting activity after 7 months. Precontemplators who received self-help smoking cessation materials made forward changes in quitting plans and these changes seemed to follow a certain order. Forward changes in plans were differentially related to positive outcome expectations, to self-efficacy expectations depending on the quitting plan and not to changes in negative outcomes. The present study is one step in mapping the psychology of low motivation to change behavior. Introduction Oxford University Press 2000 423

A. Dijkstra and H. De Vries precontemplating smoker populations may be that might be targeted by smoking cessation interventions. heterogeneous (Crittenden et al., 1994; Dijkstra et al., 1997). That is, there may be subtypes within The present study aims to replicate the findings the group of precontemplating smokers from the Dijkstra et al. (Dijkstra et al., 1997) and subtypes might benefit from different intervencategories study with larger statistical power, adapted tions. of long-term quitting plans and adding Crittenden et al. (Crittenden et al., 1994) longitudinal analyses. Furthermore, because few distinguished between three sorts of preof data are available on the cognitive characteristics contemplators. The first and second types were not precontemplators, the set of cognitive constructs seriously thinking of quitting smoking and not which will be assessed will be expanded. That is, planning to quit, although the second type was basic constructs of Bandura s (Bandura, 1986) planning to cut down, whereas the first type was Social Cognitive Theory (SCT) will be assessed: not. The third type was seriously thinking of outcome expectations, self-efficacy expectations quitting smoking or planning to quit, but not within and self-evaluation inhibiting mechanisms. These the next 6 months. In a similar vein, Dijkstra psychological factors are thought to determine et al. (Dijkstra et al., 1997) developed a short precontemplators quitting plans and, thus, inter- questionnaire assessing precontemplators long- ventions will have to aim at changing these factors. term quitting plans. Within a sample of smokers Outcome expectations refer to the anticipated gain who were not planning to quit at least within the or loss that will follow quitting smoking. On next 6 months, they distinguished between: (1) theoretical (Bandura, 1986, 1997) and empirical grounds (Dijkstra, 1998a,b), several sorts of outsmokers who were planning to quit within 1 year, come expectations can be distinguished. Self- (2) smokers who were planning to quit within 5 efficacy expectations refer to a judgement of the years, (3) smokers who were planning to quit personal ability to quit smoking. Also, several sorts somewhere in the future but not within 5 years, of self-efficacy expectations can be distinguished (4) smokers who were planning to never quit and (Dijkstra and De Vries, 2000). Two self-evaluation (5) smokers who felt none of these plans was inhibiting mechanism can be distinguished: the representative of their own long-term quitting plan. frequency of worrying thoughts and the adherence A proportion of the latter group of smokers is to excuses to smoke. Both constructs refer to the probably planning to cut down on cigarettes. functional regulation of information input (Dijkstra The fact that precontemplators with different et al., 1999a). That is, when the information input quitting plans exist gives little insight in the is decreased and distorted (low frequency and many psychological factors that will have to be changed excuses, respectively), the salience of expected by smoking cessation interventions. Therefore, outcomes, such as health damage through smoking, the psychological characteristics of smokers with is lowered. different plans are of importance. The three types The first goal of the present study is to map of Crittenden et al. (Crittenden et al., 1994) differed different sorts of positive and negative outcome significantly on the motivation to quit and the expectations, self-efficacy expectations and selfconfidence to be able to quit. However, in a evaluation inhibiting processes in precontemplasecond study they showed that these types differed tors. The second goal is to explore the cognitive significantly only on motivation to quit (Crittenden characteristics of precontemplators with different et al., 1998). The subtypes of Dijkstra et al. plans with regard to their smoking behavior. The (Dijkstra et al., 1997) differed significantly on the third goal of this study is to assess the predictive perceived pros of quitting but not on the perceived validity of these plans. The final goal of this study cons and self-efficacy. Thus, these data indicate is to investigate the cognitive changes smokers that the subtypes differed on psychological factors undergo when they change quitting plans. 424

Subgroups of precontemplating smokers Method (plans 3, 4, 5, 6 and 7), contemplation (plan 2) or preparation (plan 1). Smokers who had quit for the Procedure and design last 24 h were considered to be in the action stage. Smokers with low readiness to change were Intention to quit recruited by advertisements in local newspapers Intention was measured with a composite of three throughout the Netherlands. The recruitment 10-point scales: To what extent do you intend to procedure was the same as used in an earlier study quit smoking: (1) within the next 6 months; (2) on smokers with low readiness to change (Dijkstra within the next 5 years; (3) ever? The items could et al., 1998c). After smokers had phoned the be scored from not at all (1) to very much (10). university in order to register (n 1000), they The composite intention score was the average were sent the pre-test questionnaire which could item score (Cronbach s α 0.79). be returned in a pre-paid envelope. After 2 weeks, 915 (91.5%) pre-test questionnaires had been Quitting behavior returned. Forty-five of these questionnaires were Quitting behavior was measured with a one point excluded, because the respondents only smoked a prevalence measure: Have you been smoking pipe or cigars, or because they did have plans to during the last 7 days? (even one puff) (yes/no) quit within the next 6 months. This resulted in 861 and a retrospective report of a quit attempt: Have respondents at T 1 (86.1%). These smokers were you engaged in a quit attempt since the last randomly assigned to one of three experimental measurement? (yes/no). conditions offering different smoking cessation Smoking behavior and quitting history self-help materials by mail or one no-information control condition. The results on the efficacy of Smoking behavior was measured by asking the self-help materials are published elsewhere smokers how many years they had been smoking (Dijkstra et al., 1999b). Six months after the and how many cigarettes they smoked on the intervention, these 861 participants were sent the average. Nicotine dependence was assessed using post-test questionnaire (T 2 ) of which 751 (89%) the Fagerström Test for Nicotine Dependence were returned. (FTND) (Heatherton et al., 1991) which assesses smoking habits: How much do you smoke? How Questionnaire soon after awaking? Is it hard not to smoke in public places? Do you smoke when you are ill? Quitting plans Do you smoke more in the morning and which Precontemplation quitting plans were assessed by cigarette is most difficult to give up? The minimum confronting smokers with different long-term plans possible score was 0, the maximum 10 (α 0.71). with regard to smoking cessation (Dijkstra et al., Quitting history was measured by asking whether 1997, 1998a). They were asked to score the one they had ever engaged in a 24 h quit attempt and plan that was the most similar to their own quitting in the last 12 months. plan: Are you: (1) planning to quit within the next month; (2) planning to quit within the next Demographics 6 months; (3) planning to quit within the next Demographics measured were sex, age and level of 12 months; (4) planning to quit within the next 5 education. Level of education was categorized as years; (5) planning to quit somewhere in the future; low, medium or high. In the diverse schooling (6) planning to never quit, but planning to cut system in the Netherlands, low level of educadown on cigarettes; (7) planning to never quit and tion refers to vocational training, medium level not planning to cut down on cigarettes. The participants, then, were categorized in one of three stages of readiness to change: precontemplation to advanced vocational training and high level to college/university training. The following four psychological constructs were 425

A. Dijkstra and H. De Vries assessed: positive outcome expectations, negative such as, thinking of all the benefits of quitting ; outcome expectations, self-efficacy expectations and Relapse self-efficacy (five items; α 0.90), and self-evaluation inhibiting thoughts. which assesses the confidence to recover from a Positive and negative outcome expectations (re)lapse. All items were measured on a sevenpoint scale and could be scored from not sure at The items of these scales were validated in earlier all I am able to ( 3) to very sure I am able to studies (Dijkstra et al., 1996, 1997) and referred ( 3). Emotional, Social, Skill and Relapse selfefficacy to possible gain (positive outcome expectations) items were introduced as follows: Imagine or loss (negative outcome expectations) smokers you are engaging in a serious quit attempt. Are anticipated as a consequence of quitting and were you able to.... In the case of Relapse self-efficacy in the following format: If I quit smoking, it was asked: Are you able to maintain your quit then.... The items could be scored from not sure attempt after an initial lapse when you have been or not expecting a certain outcome (0) to a refraining from smoking for...(a specified strong expectation of the outcome (3). Earlier period).... studies showed that different factors could be distinguished within the positive outcome expectations Self-evaluation inhibiting processes (Dijkstra et al., 1998b). Thus, the following Two measures of self-evaluation inhibiting pro- scales assessing positive outcome expectations cesses or the the functional regulation of were formed: Long-term physical outcomes (three information input, were used. The first measure items; α 0.91); Short-term physical outcomes assessed the frequency of worrying thoughts (eight (three items; α 0.74); Social outcomes (three items; α 0.88). The eight items of this scale items; α 0.77); and Self-evaluative outcomes were derived from interviews with smokers and (three items; α 0.76). Two sets of items were the frequency answer format was adopted from used to assess the negative outcome expectations Prochaska s Processes of Change questionnaire (Dijkstra et al., 1998b). The first set referred to (Prochaska et al., 1988). The items referred to the the anticipation of loss of functions of smoking, frequency of thoughts and intrusions on the health such as the loss of a means to relax or a means to damaging effects of smoking. For example, the cope with anger (nine items; α 0.84). The second frequency of: thinking about the effects of smok- set assessed the expected withdrawal symptoms. ing in your body or the frequency of thinking Within this set, two factors could be distinguished: about how my lungs will look. The items could expected withdrawal symptoms (four items; α be scored from never (0) to very often (4). The 0.81) and expectations of physical complaints (four second measure assessed excuses to smoke (seven items; α 0..72). items; α 0.76). This scale was tested and Self-efficacy expectations validated in an earlier study (Dijkstra et al., 1999a). The items could be scored from I do not agree Self-efficacy was assessed using the 20 selfefficacy ( 2) to I do agree ( 2) and were formulated to items developed by Dijkstra and finish the sentence: Smoking can make me ill, De Vries (Dijkstra and De Vries, 2000). From but.... The items gave reasons (or excuses) why these items four self-efficacy scales were formed: it was alright to smoke, despite the well-known Emotional self-efficacy (four items; α 0.88), detrimental effects. A typical excuse may be true which assesses the confidence to be able to refrain in itself but may only address half the truth (e.g. from smoking in emotional situations; Social selfefficacy I know heavy smokers who live a long and healthy (four items, α 0.90), which assesses life or I am exposed to so many risks in my life ) confidence in social situations; Skill selfefficacy or it may actually not be based on reality (e.g. (seven items; α 0.85), which assesses If smoking were really that bad, it would be confidence to use specified non-smoking skills, prohibited ). 426

Subgroups of precontemplating smokers Statistical analyses Firstly, the scale characteristics of the 14 cognitive measures were assessed. Secondly, Pearson correlations among the scales were computed. The nicotine dependence scale and the intention to quit composite were added to the correlation matrix to further assess whether the relations were in the expected directions. Thirdly, smokers with different plans were compared on cognitive variables, using analyses of variance. Since the relationships between quitting plans and cognitive variables may differ for smokers with different demographic, smoking behavioral and smoking history charac- teristics, several interactions were tested. In the case of a significant interaction, the analyses were stratified by the demographic, smoking behavioral or smoking history variable. Fourthly, the predictive validity of the long-term quitting plans was tested using point prevalence quitting, a retrospective report of quitting and forward plan change as outcome variables. The former analyses were conducted using logistic regression, while the latter analysis was tested using χ 2 analysis. Fifthly, the changes in the cognitive variables smokers undergo when they move forward to a shorter-term quitting plan were assessed. In five sets of analyses, one for each pre-test long-term quitting plan, post-test scores on the cognitive variables between smokers who moved forward and smokers who did not move forward were compared. The pre-test scores on the cognitive variables were entered as covariates. All tests in the present study were two-tailed and α was set at 0.05. In the longitudinal tests, intervention condition was entered as a covariate to control for possible differential effects of the interventions. Sample characteristics Of the 861 respondents, 23% were planning to never quit and not planning to cut down, 22% were planning to never quit, only planning to cut down, 34% were planning to quit in the future but not within the next 5 years, 16% were planning to quit within the next 5 years and 6% were planning to quit within the next year. Furthermore, 63% were female, 29% had a low level of education, 45% had a medium level and 26% a high level of education, and the mean age was 41.7 years (SD 12.9; range 16 81 years). On average, they smoked 21.5 cigarettes a day (SD 10.1; range 1 80 cigarettes) and they had smoked for 24.5 years (SD 12.9; range 1 70 years). Thirty-one percent had never engaged in a quit attempt, while 85% had not engaged in a quit attempt in the last 12 months. Scale characteristics and Pearson correlation s among the scales. Most scales had good internal consistency; only the Cronbach s α of the Excuses scale was below 0.70. To explore and validate the relations among the scales, Pearson correlations were computed (Table I). Correlations among the four Positive outcomes scales ranged from 0.39 to 0.58, indicating that the scales measure distinct but related constructs. Correlations among the three Negative outcomes scales ranged from 0.45 to 68, indicating that the scales measure distinct but related constructs, although the latter high correla- tion indicate that the scales have a clear overlap. The correlations among Positive outcomes scales and the Negative outcomes scales were all signi- ficant but low ( 0.21), thereby supporting the distinction between both concepts. The correlations of Positive outcomes scales with Self-efficacy scales were all non-significant, while Negative outcomes scales had negative correlations with the Self-efficacy scales. Thus, the more negative outcomes of quitting a smoker perceives, the lower the smoker s confidence to be able to quit. The Worrying thoughts scale correlated positively with the Positive outcomes scales and positively but low with the Negative outcomes scales. The former finding might indicate that the more positive outcomes smokers perceive (meaning the stronger they anticipate the relief from the present negative effects of smoking through quitting) the more frequently they think of the damaging physical effects of smoking. The Excuses scale had a negative correlation with the Positive outcomes scale. Excuses might moderate the perceived bene- fits from quitting, that is, lower the salience of the 427

A. Dijkstra and H. De Vries Table I. Pearson correlations among the four sorts of positive outcome expectations, three sorts of negative outcome expectations and four types of self-efficacy, and frequency of worrying thoughts, excuses to smoke, Fagerstrom nicotine dependence score and intention to quit 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1 Physical short POU 2 Physical long POU 0.58 a 3 Social POU 0.42 a 0.00 4 Self-evaluative POU 0.39 a 0.39 a 0.45 a 5 Loss of function NOU 0.18 a 0.17 a 0.14 a 0.17 a 6 Withdrawal NOU 0.13 a 0.15 a 0.14 a 0.21 a 0.68 a 7 Physical NOU 0.12 a 0.10 a 0.10 a 0.19 a 0.45 a 0.53 a 8 Emotional SE 0.06 0.02 0.05 0.04 0.38 a 0.42 a 0.25 a 9 Social SE 0.06 0.00 0.02 0.02 0.24 a 0.24 a 0.14 a 0.63 a 10 Skill SE 0.29 a 0.25 a 0.20 a 0.18 a 0.18 a 0.14 a 0.11 a 0.44 a 0.47 a 11 Relapse SE 0.04 0.00 0.04 0.00 0.17 a 0.17 a 0.06 0.24 a 0.25 a 0.25 a 12 Worrying thoughts 0.48 a 0.47 a 0.48 a 0.56 a 0.18 a 0.21 a 0.19 a 0.05 0.01 0.22 a 0.02 13 Excuses 0.24 a 0.30 a 0.22 a 0.19 a 0.08 0.02 0.03 0.11 a 0.13 a 0.14 a 0.07 0.28 a 14 Fagerstrom 0.08 0.00 0.04 0.02 0.30 a 0.37 a 0.26 a 0.35 a 0.25 a 0.24 a 0.17 a 0.04 0.06 15 Intention 0.37 a 0.30 a 0.32 a 0.45 a 0.03 0.02 0.02 0.12 a 0.16 a 0.33 a 0.03 0.36 a 0.27 a 0.11 a a P 0.05. POU positive outcome expectations; NOU negative outcome expectations; SE self-efficacy expectations. perceived negative effects of smoking. The FTND correlated positively with the Negative outcomes scales and negatively with the Self-efficacy scales. Thus, the more dependent a smoker is, the more negative outcomes of quitting he or she anticipates and the lower the self-efficacy. Only the Negative outcomes scales had no correlation with intention to quit. All these relationships are in expected and interpretable directions. Results Cognitive characteristics of precontemplators with different quitting plans Smokers with different long-term quitting plans were compared on the cognitive characteristics (Table II). All analyses are corrected for differences in demographics, smoking behavior and quitting history by entering these variables as covariates. The overall analyses showed that smokers with different plans differed significantly on all positive outcomes (P 0.001), on expected withdrawal symptoms only in smokers who had made a quit attempt (P 0.05), on Emotional and Skill self- efficacy (P 0.01), and on Social self-efficacy only in medium (P 0.001) and highly (P 0.05) addicted smokers, and on both self-evaluation inhibiting processes (P 0.001) and intention to quit (P 0.001). Thus, the quitting plans had no significant relationships with expected loss of function, expected withdrawal symptoms only in smokers who had made no quit attempt, expected physical symptoms, Social self-efficacy in light smokers and Relapse self-efficacy. Looking more closely at the data, the following contrasts and interactions were detected. With regard to the positive outcome expectations, the data show that the more proximal and the more concrete the quitting plans, the more positive outcomes smokers expected. In particular, smokers who were planning to never quit and not planning to cut down perceived fewer of all sorts of positive outcomes than other smokers with other plans. Furthermore, the relation between the quitting plans and self-evaluative outcomes differed significantly for males and females: females with concrete plans (quitting within 1 and 5 years) anticipated more self-evaluative outcomes than males with such plans. Moreover, self-evaluative outcomes were the 428

Subgroups of precontemplating smokers Table II. Cognitive characteristics in standardized T scores (mean 50) of smokers with different plans with regard to changing their smoking behavior Individual quitting plans 1. Planning to 2. Planning to 3. Planning to quit 4. Planning to 5. Planning to P value Tukey contrasts never quit and never quit and in the future quit within 5 quit within 1 year between not to cut down only to cut down but not within years but not but not within 6 subsequent plans (n 194) (n 187) 5 years within 1 year months (n 54) (n 290) (n 136) Positive outcomes long-term physical 46.2 49.2 50 53.8 55.1 0.001 1 2; 3 4 short-term physical 44.5 48.4 51 55.2 55 0.001 1 2 3 4 self-evaluative females 44.6 49.5 50.8 56.1 69.2 0.001 1 2; 3 4 5 males 43.9 48.5 47.7 48.9 57.2 0.001 1 2; 4 5 social 45.4 49 50.4 53.5 56.1 0.0011 2; 3 4 Negative outcomes loss of function 49.8 51.4 49.2 47.9 48.7 0.42 withdrawal quit attempt 57 57.7 50.3 52 50.5 0.014 2 3 no quit attempt 49.4 50.3 50 50.5 50.7 0.63 physical complaints age 16 35 51.5 48.7 48.3 48 50.4 0.23 age 36 46 49.8 52.2 51.5 52.1 47.8 0.31 age 47 84 46.9 51 50.3 51.5 53.5 0.18 Self-efficacy emotional situations 48.2 51.8 50.1 51.7 50.9 0.003 1 2 social situations FTND 1 4 51.3 52.8 51.5 55.3 53.6 0.10 FTND 5, 6 43.6 51.3 52 52.7 52.4 0.001 1 2 FTND 7 10 45.1 47.4 46.2 52.2 43.7 0.02 3 4 5 skill application 45.2 49.5 50.5 53.9 54.1 0.001 1 2; 3 4 relapse recovery 49.3 50.4 50.3 50.4 50.7 0.82 Additional measures worry 1 18 years smoked 46.2 51 49.4 52.3 58.2 0.001 4 5 19 28 years smoked 46.8 51.9 50.6 54.4 52.4 0.007 1 2 29 70 years smoked 43.7 50.1 50.1 54.6 64.6 0.001 1 2; 4 5 excuses 52.8 51 49.6 46.9 45.1 0.001 3 4 intention to quit quit attempt 40.1 50 54.5 63 67.4 0.001 1 2 3 4 5 no quit attempt 40.1 44.1 50.5 61.1 67.1 0.001 1 2; 3 4 only positive outcomes that discriminated between smokers who planned to quit within 1 year and those who planned to quit within 5 years. The data on the perceived negative outcomes of quitting showed that only the relation between quitting plans and Withdrawal symptoms was significant and that this was only the case for those who had engaged in a quit attempt: smokers in both groups who were not planning to quit anticipated many withdrawal symptoms, only when they had engaged in a quit attempt. The relation between quitting plans and Physical complaints depended significantly on age although no main effects of quitting plan occurred in the separate age groups: older smokers (47 84 years of age) who were not planning to quit and not planning to 429

A. Dijkstra and H. De Vries in smokers with other plans. Furthermore, quitting plan was a significant predictor of engaging in a quit attempt since pre-test (P 0.001). Smokers who were planning to never quit and not planning to cut down scored especially low (6.6%), whereas this percentage in smokers who were planning to quit within the next 1 year was 43.5%. Quitting plan was a significant predictor of forward plan change (P 0.001). The data can be summarized as follows. With regard to four of the five quitting plans, about half of the smokers had the same plan after 7 months; only among smokers who were planning to quit within 1 year there was a lower percentage (28%) who had made no change in plans. Furthermore, in four of the five quitting plans a backward change was possible. The per- centages of backward change were around 15% in three plans and 8% in one plan. Thus, larger percentages changed forward. In four of the five plans the highest percentage forward change was to the subsequent plan. About 55% of smokers who were planning to quit within 1 year made a forward change in plans, of whom almost half had quit smoking. cut down anticipated fewer physical symptoms, whereas in the intermediate age group (36 46 years of age), it was smokers who planned to quit within 1 year who anticipated fewer physical symptoms. In the youngest age group (16 35 years of age), only very small differences between smokers with different plans occurred. With regard to Emotional self-efficacy, only smokers who were planning to never quit and not planning to cut down scored significantly lower. The relation of Social self-efficacy with the different quitting plans was a function of the extent to which someone was nicotine dependent. Medium dependent smokers who were planning to never quit and not planning to cut down scored lower than smokers with other plans. In smokers who scored high on nicotine dependence, all but the smokers who planned to quit within 5 years scored low, i.e. below the mean of 50. Skill selfefficacy gradually increased as smokers had a more proximal plan to quit. The relation between worrying thoughts and quitting plans depended on the number of years smoked. Smokers who had smoked for the highest number of years (29 70 years) and were planning to quit within the next year scored very high, compared to smokers with other plans. Smokers who smoked for 19 28 years and were planning to quit within 1 year, in contrast, scored lower than smokers who were planning to quit within the next 5 years. With regard to excuses to smoke, the data show a steady decrease as smokers adhere to a more proximal plan to quit. Intention to quit was a strong discriminator between the different quitting plans, especially in smokers who had quit in the past. Predictive validity of the different quitting plans The analyses on predictive validity are corrected for differences in demographics, smoking behavior and quitting history (Table III). Quitting plan was a significant predictor of point prevalence quitting (P 0.001). Specifically, smokers who were planning to quit within the next 1 year scored high: 19.6% after seven months versus 1.8 5.9% Cognitive changes during forward changes in quitting plans Smokers with a certain quitting plan at pre-test who made a forward change in plans were compared to smokers who made no forward change in plans on cognitive changes from pre-test to post-test (Table IV). Significant increases in positive outcome expectations were related to a forward change in plans in three subtypes: in smokers in both groups with plans to never quit and in smokers who were planning to quit somewhere in the future. In smokers with concrete plans (to quit within 1 and 5 years), only significant increases in the selfevaluative positive outcomes were associated with a forward change in plans. Changes in negative outcome expectations were hardly related to forward changes in quitting plans. Significant increases in self-efficacy were related to a forward change in plans in three groups of smokers: in smokers who were only planning to 430

Subgroups of precontemplating smokers Table III. Predictive validity of the plans with regard to changing smoking behavior Individual quitting plans Planning to never Planning to never Planning to quit Planning to quit Planning to quit Total sample P value quit and not to quit, only to in the future within 5 years within 1 year (n 761; 100%) cut down cut down but not within but not within but not within (n 167; 21.5%) (n 173; 22.8%) 5 years 1 year 6 months (n 257; 33.9%) (n 118; 15.7%) (n 46; 6.1%) Seven days quit 1.8 4.6 1.6 5.9 19.6 4.1 0.001 24 h quit attempt 6.6 16.8 13.6 24.6 43.5 16.3 0.001 Plan at post-test 0.001 never 58.4 8.2 3.5 0.8 0 15.7 cut down 16.8 47.4 12.6 5.1 8.7 20 ever, 5 years 16.8 17.5 48 12.7 4.3 26.1 5 years 2.5 11.1 18.9 47.5 2.2 17.1 1 year 1.2 3.5 7.5 14.4 28.3 7.6 6 months 0.6 2.9 3.9 10.2 21.7 5.1 1 month 0 4.1 3.1 2.5 10.9 3.1 quit for 24 h 3.7 5.3 2.4 6.8 23.9 5.3 Table IV. Comparing post-test means of smokers with a forward change in plans to smokers with no forward change in plans, on cognitive measures Pre-test plans Planning to never Planning to never Planning to quit in Planning to quit Planning to quit quit and not to quit, only to the future but not within 5 years but within 1 year but not cut down cut down within 5 years not within 1 year within 6 months NC FC NC FC NC FC NC FC NC FC Cognitive variables n 89 n 68 n 91 n 73 n 155 n 88 n 72 n 42 n 20 n 26 Positive outcomes long-term physical 1.35 1.60 a 1.81 1.90 1.19 2.11 a 2.28 2.30 2.29 2.20 short-term physical 0.90 1.20 b 1.34 1.51 a 1.58 1.81 c 1.86 2.00 1.90 1.82 self-evaluative 0.15 0.30 b 0.40 0.80 d 0.54 0.90 d 0.81 1.45 d 1.22 1.69 b social 0.88 1.20 b 1.34 1.58 b 1.47 1.74 c 1.77 1.89 2.01 2.05 Negative outcomes loss of function 0.83 0.85 1.04 0.89 a 0.94 0.86 0.89 0.85 0.86 0.78 withdrawal 1.03 1.29 b 1.37 1.24 1.33 1.19 1.30 1.19 1.37 0.93 a physical complaints 0.45 0.54 0.43 0.31 a 0.48 0.37 a 0.43 0.34 0.43 0.23 Self-efficacy emotional situations 0.58 0.56 0.65 0.23 b 0.49 0.06 c 0.23 0.16 a 0.60 0.53 b social situations 0.54 0.51 0.49 0.02 b 0.24 0.14 b 0.32 0.51 0.80 1.02 d skill application 0.21 0.20 b 0.39 0.72 b 0.44 0.91 d 0.87 1.10 0.63 1.27 b relapse recovery 0.70 0.41 0.65 0.42 0.73 0.43 a 0.56 0.28 0.33 0.27 Additional measures worry 0.81 0.85 1.18 1.35 b 1.17 1.48 d 1.47 1.60 1.91 1.96 excuses 0.44 0.27 0.22 0.20 0.15 0.07 b 0.16 0.31 0.16 0.07 intention to quit 3.66 10.30 d 6.98 17.30 d 11.65 21.40 d 19.13 26.58 d 20.07 28.04 c a P 0.10; b P 0.05; c P 0.01; d P 0.001. NC no forward change; FC forward change. 431

A. Dijkstra and H. De Vries cut down, in smokers who were planning to quit The question to what extent precontemplators somewhere in the future and those who were are a homogenous group was central in the present planning to quit within 1 year. study. The above results indicate that on the Significant changes in self-evaluation inhibiting cognitive variables which are considered to be processes occurred especially in smokers who were related causally to behavior change large differences planning to quit somewhere in the future, who among precontemplators exist. However, it made a forward change in the quitting plan. They is important to show that these cognitive differences had significantly more worrying thoughts and they are related to actual behavior. Therefore, used significantly fewer excuses. For all groups of the predictive validity of quitting plans is a more smokers, a forward plan change was related to a stringent test of the homogeneity of this group. significantly larger increase in intention to quit. With regard to the point prevalence quitting measure, specifically smokers who were planning to Discussion quit within the next year were more active than the others. It could be questioned to what extent The goal of the present study was to investigate these smokers can be classified as precontemplawhether subtypes of precontemplators could be tors. That is, early models of the stages of change distinguished based on their long-term quitting defined precontemplators as smokers who were plans. Before comparing the smokers with different not planning to quit within the next year in contrast plans we studied some central cognitive constructs with contemplators, who were planning to quit from Bandura s (Bandura, 1986) SCT. The internal within this term (DiClemente et al., 1985; consistencies of the scales were good and all Prochaska et al., 1985; Wilcox et al., 1985). When relations among the scales were in the expected we accept the high scores on the frequency of directions. Thus, it seems that precontemplators worrying thoughts of precontemplators with the can be validly described in terms of positive 1 year quitting plan as being an indication of and negative outcome expectations, self-efficacy their openness to information on the effects of expectations and self-evaluation inhibiting pro- smoking, this further supports the notion that they cesses. are more like contemplators (Prochaska et al., The first finding concerned the differences 1992). Future studies including contemplators between and similarities of precontemplating might further study the best classification algorithm smokers with different quitting plans. The data in Dutch smokers. The data with regard to the with regard to the cognitive measures showed retrospectively reported quit attempts showed a that smokers with different plans differed on the more linear relation between quitting plans and positive outcome expectations, self-efficacy quitting activity: The more concrete and the more expectations, self-evaluation inhibiting processes proximal the quitting is planned, the higher the and intention to quit. Thus, generally speaking, probability that precontemplators will engage in a the more rewards precontemplators expect from quit attempt. These data on the predictive validity quitting, the more confidence they have that they seem to support the notion that relevant subgroups are able to quit, and the less bias in how they of precontemplators might be distinguished based process information (high worry frequency and on their quitting plans. few excuses), the more concrete and proximal their The data on the changes in quitting plans showed plans to quit smoking. There was no relation that, after 7 months, in four of the five quitting between quitting plans and negative outcome plan groups, around 50% made no detectable expectations. This is in line with the expectations change. Again, smokers who were planning to quit of the negative outcomes having little to do with within the next year deviated: only 28% made no the early phases of the process of behavior change change. Furthermore, in all five groups, smokers (Prochaska, 1994; Dijkstra et al., 1996). who made a forward change in plans had the 432

Subgroups of precontemplating smokers highest probability of adhering to the subsequent cessing; the excuses. With regard to negative (more concrete and more proximal) quitting plan. outcome expectations, no differences occurred This might mean that in becoming more motivated between precontemplators who made a forward to quit, precontemplators follow a certain order in change in plans and those who made no forward plans. Furthermore, the fact that precontemplators change. This further underlines the notion that the who were planning to quit within 1 year were perception of the negative outcomes of behavior about 4 times as probable to have moved forward change is not related to the motivational change to the action stage a finding overlapping and process in precontemplators (Prochaska et al., parallel with the point prevalence quitting 1994). Increases in self-efficacy were, firstly, figures further supports this notion. Although we relevant in smokers who were only planning to certainly do not advocate that the five quitting cut down. Thus, an increase in self-efficacy might plans refer to stages within the precontemplation make these smokers more confident that they are stage, smoking cessation interventions targeted at able to quit completely. As a result they might precontemplators might take into account the fact adhere to a new complete-quitting plan. Interthat most precontemplators do not jump to the ventions targeted at smokers who are only planning contemplation stage but rather make small changes to cut down might communicate self-efficacy to more concrete and proximal plans to quit. enhancing information. Secondly, the clearest The present data on the cognitive changes which changes in self-efficacy occurred in smokers with accompany forward changes in plans might further a vague quitting plan, to quit somewhere in the increase our insight in the change process and the future. Again, increases in self-efficacy might make changes to be brought about by interventions in quitting a realistic and feasible option for these precontemplators. In interpreting the data on the smokers. Together with the motivating power of cognitive changes, the theoretical assumption is the perceived positive outcomes of quitting, this that positive, negative and self-efficacy expectamight make them adhere to a new and more tions and self-evaluation inhibiting processes are concrete quitting plan. The same principle could causes, not effects, of the formation of quitting account for precontemplators who were planning plans. A forward change in plans, first, seemed to to quit within 1 year. be accompanied by increases in several sorts of The following limitations of this study must be positive outcomes. In precontemplators with contaken into account. First of all, the sample of crete plans to quit within the next 5 years or the next year only the self-evaluative outcomes precontemplators was recruited re-actively. It is changed. The perception of self-evaluative outrespondents. However, the recruitment advertise- plausible that this led to a certain selection of comes is influenced by the active and unbiased processing of information on physical and social ments included the statement that respondents did outcomes (Dijkstra et al., 1999a). Therefore, it not have to quit in order to join the study. Reactions might be concluded that offering information on of smokers in the telephone interviews further physical and social outcomes is important in supported our idea that many respondents were precontemplators with one of the first three still resistant to change and had very low motivation (non-quitting or vague) quitting plans, whereas in to change. Secondly, although only 11% of the precontemplators with the concrete quitting plans pre-test respondents dropped out, this may have the active and unbiased cognitive processing of further led to a selective sample of precontempla- this information which might already be in tors. Thirdly, the precontemplators in this study memory is more important. The cross-sectional had received smoking cessation materials just after data, indeed, show that precontemplators with the pre-test. Although the longitudinal statistical concrete quitting plans score significantly lower analyses were controlled for effects which might on our measure of (un)biased information pro- be caused by the intervention conditions, it remains 433

A. Dijkstra and H. De Vries obscure to what extent this has influenced the Dijkstra, A., Bakker, M. and De Vries, H. (1997) Subtypes within a precontemplating sample of smokers: A preliminary results. extension of the stages of change. Addictive Behaviors, 22, In conclusion, in smoking, precontemplators are 327 337. a heterogeneous group and relevant subgroups can Dijkstra, A., Roijackers, J. and De Vries, H. (1998a) Smokers in four stages of readiness to change. Addictive Behaviors, be distinguished by their plans to quit smoking. 23, 339 350. Precontemplators who receive self-help smoking Dijkstra, A., De Vries, H. and Roijackers, J. (1998b) Computerized tailored feed-back to change cognitive cessation materials can make forward changes in determinants of smoking: a Dutch field experiment. Health quitting plans and these changes seem to follow a Education Research, 13, 197 206. certain order. Forward changes are mainly related Dijkstra, A., De Vries, H. and Roijackers, J., Breukelen, van, G. (1998c) Computerized tailored feed-back to stimulate to positive outcome expectations, to self-efficacy precontemplators to quit smoking: three basic efficacy expectations depending on the quitting plan and questions. Health Psychology, 17, 513 519. not to changes in negative outcomes. The present Dijkstra, A., De Vries, H., Kok, G. and Roijackers, J. (1999a) Self-evaluation and motivation to change: Social cognitive study, thus, is one step in mapping the psychology constructs in smoking cessation. Psychology and Health, 14, of low motivation to change behavior. 747 759. Dijkstra, A., De Vries, H. and Roijackers, J. (1999b) Targeting smokers with low readiness to change with tailored and Acknowledgements non-tailored self-help materials. Preventive Medicine, 28, 203 211. Etter, J. F., Perneger, T. V. and Ronchi, A. (1997) Distribution This research was supported by a grant from the of smokers by stage: international comparison and association Dutch Cancer Society. with smoking prevalence. Preventive Medicine, 26, 580 585. Heatherton, T. F., Kozlowski, L. T., Frecker, R. C. and Fagerström, K. O. (1991) The Fagerström Test for Nicotine References Dependence: a revision of the Fagerström Tolerance Questionnaire. British Journal of Addiction, 86, 1119 1127. Bandura, A. (1986) Social Foundations of Thought and Action; Prochaska, J. O. (1994) Strong and weak principles for A Social Cognitive Theory. Prentice-Hall, Englewood progressing from precontemplation to action on the base of Cliffs, NJ. twelve problem behaviors. Health Psychology, 13, 1 5. Bandura, A. (1997) The Exercise of Control. Freeman, New Prochaska, J. O., DiClemente, C. C., Velicer, W. F., Ginpil S. York. and Norcross, J. C. (1985) Predicting change in smoking Crittenden, K. S., Manfredi, C., Lacey, L., Warnecke, R. and status for self-changers. Addictive Behaviors, 10, 395 406. Prochaska, J. O., Velicer, W. F., DiClemente, C. C. and Fava, Parsons, J. (1994) Measuring readiness and motivation to J. (1988) Measuring processes of change: applications to the quit smoking among women in public health clinics. Addictive cessation of smoking. Journal of Consulting and Clinical Behaviors, 19, 497 507. Psychology, 56, 520 528. Crittenden, K. S., Manfredi, R. B., Warnecke, R., Cho, Y. I. Prochaska, J. O., DiClemente, C. C. and Norcross, J. C. (1992) and Parsons, J. A. (1998) Measuring readiness and motivation In search of how people change, applications to addictive to quit smoking among women in public health clinics: behaviors. American Psychologist, 47, 1102 1114. predictive validity. Addictive Behaviors, 23, 191 199. Prochaska, J. O., Velicer, W. F., Rossi, J. S., Goldstein, M. G., DiClemente, C. C., Prochaska, J. O. and Gibertini, M. (1985) Marcus, B. H., Rakowski, W., Fiore, C., Harlow, L. L., Self-efficacy and the stages of self-change of smoking. Redding, C. A., Rosenbloom, D. and Rossi, S. R. (1994) Cognitive Therapy and Research, 9, 181 200. Stages of change and decisional balance for 12 problem Dijkstra, A. and De Vries, H. (2000) Self-efficacy with regard behaviors. Health Psychology, 13, 39 46. to different tasks in smoking cessation. Psychology and Wilcox, N. C., Prochaska, J. O., Velicer, W. F. and DiClemente, Health, in press C. C. (1985) Subject characteristics as predictors of self- Dijkstra, A., De Vries, H. and Bakker, M. (1996) The pros and change in smoking cessation. Addictive Behaviors, 10, cons of quitting, self-efficacy and the stages of change 407 412. in smoking cessation. Journal of Consulting and Clinical Psychology, 4, 758 765. Received on July 16, 1999; accepted on December 18, 1999 434