CRITICALLY APPRAISED PAPER FOCUSED QUESTION For individuals with memory and learning impairments due to traumatic brain injury, does use of the self-generation effect (items self-generated by the subject) improve recall and performance in functional tasks when compared to the use of a provided condition (items read or otherwise provided to the subject)? Goverover, Y., Chiaravalloti, N., & DeLuca, J. (2010). Pilot study to examine the use of selfgeneration to improve learning and memory in people with traumatic brain injury. American Journal of Occupational Therapy, 64, 540 546. http://dx.doi.org/10.5014/ajot.2010.09020 CLINICAL BOTTOM LINE: The results of this study indicate that steps to complete functional tasks learned using a selfgenerated learning approach (i.e., directions for a task were given with a key word omitted, leaving the participant to generate the missing word in a step of a task) were recalled at a significantly higher rate than those learned using the provided condition (i.e., when all directions were given to the subject with no omissions). Self-generated learning addresses difficulties that occur during the initial acquisition of information, which are often observed in individuals with traumatic brain injury (TBI). These difficulties often lead to functional deficits in both memory and learning. As an intervention, self-generation could serve as a compensatory approach for these individuals to become more independent in functional tasks. Although this study was based on previous successful research studies on the self-generation learning effect, this is currently the only evidence suggesting its use with individuals with TBI using functional tasks. Considering the small sample size, the results of this study should be generalized cautiously. However, occupational therapy practitioners could consider this approach for individuals with cognitive impairments, such as those that can result from TBI, to improve recall and performance in functional tasks. RESEARCH OBJECTIVE(S) List study objectives. The researchers focused on the use of self-generation on learning and memory of functional tasks in both individuals with TBI and those without neurological impairment. 1
DESIGN TYPE AND LEVEL OF EVIDENCE: Design type: Quantitative, within-subjects design with counterbalancing. It is a 2 () 2 (condition) 3 (time) factorial design. Level of evidence: II Limitations (appropriateness of study design): Was the study design type appropriate for the knowledge level about this topic? Circle yes or no, and if no, explain. YES/NO SAMPLE SELECTION How were subjects selected to participate? Please describe. Participants were recruited for the study through the use of advertisements distributed at local support s and clinics, then screened using inclusion and exclusion criteria determined via phone interviews. Ten participants were selected for the TBI, and 15 participants were selected for the healthy control (HC). Participants within both s did not differ greatly in regards to pre-morbid intelligence, gender, and age. All participants were paid for their participation. Inclusion Criteria Participants were adults (>18 years) TBI TBI confirmed using either Documented positive computed tomography or magnetic resonance neuroimaging Documentation confirming a period of loss of consciousness ( 24 hours) Individuals were 1 year post-injury. HC Healthy individuals with no neurological disability. Exclusion Criteria Participants <18 years of age A history of neurological illness (aside from TBI for appropriate ) A history of major psychiatric illness A history of alcohol or drug abuse Severe visual or motor impairment that would interfere with the study procedures. SAMPLE CHARACTERISTICS N = 25. % Dropouts NR #/ (%) Male TBI: 10 (54.5%) HC: 15 (45.5%) 2 #/ (%) Female TBI: 45.5% HC: 54.5%
Ethnicity NR Disease/disability diagnosis Moderate or severe TBI Healthy controls Check appropriate : < 20/study 20 50/study 51 100/study 101 149/study 150 200/study INTERVENTION(S) AND CONTROL GROUPS Add s if necessary. Group 1 Healthy Control Brief Description Members of the HC were asked to recall instructions for 2 cooking tasks and 2 financial tasks. One of the cooking tasks and 1 of the financial tasks were introduced for recall using the provided condition, while the remaining tasks were introduced for recall using the self-generated condition. For the provided condition, the 2 tasks were divided into 12 separate steps necessary to perform the task. Each step was written with full directions on a notecard. The participant read each notecard only once at the initial presentation. They were asked to verbally recall the steps immediately after the initial presentation, perform the task after 30 minutes, and then again verbally recall the steps 1 week later via a telephone interview. For the self-generated condition, the 2 tasks also were divided into 12 separate steps necessary to perform the task. However, instead of having the participant simply read the steps, a key word was omitted from each of the steps written on the notecard. This omitted key word required the participant to self-generate the missing word to complete the directions for each step. The participants were then asked to recall all 12 steps immediately after the initial presentation, perform the task after 30 minutes, and then verbally recall the steps 1 week later via telephone. Setting Who Delivered? Frequency? Duration? Initial testing setting: NR Final task recall 1 week later: Via telephone with participant at home Yael Goverover, PhD, OT 3x. Recall tested immediately after initial presentations, 30 minutes later, and 1 week later via telephone interview. The initial testing took 3 hours, which included neuropsychological testing between the initial presentation/recall and the 30-minute task performance. Duration of the final task recall via telephone was not reported. Group 2 TBI Brief Description Members of the experimental (participants with TBI) were asked to recall instructions for 2 cooking tasks and 2 financial tasks in exactly the same way as the control. One of the cooking tasks and one of 3
Setting Who Delivered? Frequency? Duration? financial tasks were introduced for recall using a provided condition. For the provided condition, the individuals were given the process of the activity in 12 separate steps with full instructions. They were asked to recall the steps immediately after presentation, perform the task after 30 minutes, and then again verbally recall the steps 1 week later via telephone interview. Similarly, 1 of the cooking tasks and 1 of financial tasks were introduced for recall using a self-generated condition. For this condition, a key word was omitted from each of the 12 steps and the individual had to fill in the blank. They were asked to recall the steps immediately after the initial presentation, perform the task after 30 minutes, and then verbally recall the steps 1 week later via telephone. Initial testing setting: NR Final task recall 1 week later: Via telephone with participant at home Yael Goverover, PhD, OT 3x. Recall was tested immediately after initial presentations, 30 minutes later, and 1 week later via telephone interview. The initial testing took 3 hours, which included neuropsychological testing between the initial and 30-minute task performance. Duration of the final task recall via telephone was not reported. Intervention Biases: Circle yes or no and explain, if needed. Contamination YES/NO NR. There was no opportunity for contamination because both s, the healthy controls and individuals with TBI, participated in both conditions. Co-intervention Timing YES/NO NR. It is unclear whether either received any other occupational therapy or related rehabilitation services at the time of intervention or during the follow-up period. Additionally, the exclusion criteria did not rule out individuals receiving services or interventions, such as pharmaceutical therapies. YES/NO NR. It is unlikely for timing to be a bias because the participants were adults (ruling out maturation) and participants with TBI were excluded if they were not at least 1 year post-tbi (reducing the potential for the healing effect). Site YES/NO NR. It is unclear where the initial assessment and intervention were conducted. The participants were asked to verbally recall the task steps a final time via telephone 1 week after the initial presentation and first 2 recall tests. This change in location for the final recall test prevented the researchers for controlling for new variables within the home (i.e., distractions). This may have biased the results negatively in the participants with TBI. 4
Use of different therapists to provide intervention YES/NO Yael Goverover, PhD, OT, performed both the evaluation and intervention. MEASURES AND OUTCOMES Complete for each relevant measure when answering the evidence-based question: Name of measure, what outcome was measured, whether the measure is reliable and valid (as reported in article yes/no/nr [not reported]), and how frequently the measure was used. Neuropsychological Tests The Digit Span Subtest of the Wechsler Adult Intelligence Scale Revised Outcome measured: Cognitive performance--attention Reliability and validity: NR Frequency: Administered once, during the 30 minutes between initial presentation/recall and the performance recall session Symbol Digit Modalities Test Oral Version Outcome measured: Cognitive performance--processing speed Reliability and validity: NR Frequency: Administered once, during the 30 minutes between initial presentation/recall and the performance recall session California Verbal Learning Test Outcome measured: Cognitive performance--learning and memory Reliability and validity: NR Frequency: Administered once, during the 30 minutes between initial presentation/recall and the performance recall session Neuropsychological Testing The Digit Span Subtest of the Wechsler Adult Intelligence Scale Revised (Working Memory) Results were not significant (F[1, 24] = 0.43, p >.05) to indicate a difference in the working memory between individuals with TBI and the HC. o Symbol Digit Modalities Test Oral Version (Speed of Processing) Results were not significant (F[1, 24] = 0.14, p >.05) to indicate a difference in the speed of processing between individuals with TBI and the HC. California Verbal Learning Test (Learning and Memory) Healthy controls recalled significantly more words than individuals with TBI (F[1, 24] = 4.8, p <.05). Healthy controls recognized significantly more words than individuals with TBI (F[1, 24] = 4.8, p <.05). Three subtests of the Delis Kaplan Executive Function System Trail Making Test (Executive Functioning) Individuals with TBI took significantly longer than the healthy controls to complete this subtest (F[1, 24] = 6.2, p <.05). Verbal Fluency Test (Executive Functioning) 5
Individuals with TBI generated significantly few words than the healthy controls (F[1, 24] = 4.8, p <.05). Color Word Interference Test (Executive Functioning) Individuals with TBI required significantly more time to complete than the healthy controls (F[1, 24] = 5.1, p <.05). Main Effect CONDITION: Generated vs. provided Generated condition recall: M = 16.4, provided condition recall: M = 14.1 Generated condition recalled at a statistically higher rate: F(1, 23) = 22.9, p <.001 Medium effect size: 2 = 0.49 GROUP: TBI vs. HC No significant difference in number of task items recalled between two s: F(1, 23) = 0.24, p =.7 Small effect size: 2 = 0.06 The interaction of and condition was not significant: F(1, 23) = 1.3, p =.25 Small effect size: 2 = 0.05 TIME: Immediately vs. 30 minutes vs. 1 week Recall of items dropped significantly across time in both the generated and provided conditions: F(1, 23) = 27.9, p <.001 Medium effect size: 2 = 0.54 Significant difference indicated between recall of items after 30 minutes and 1 week after task presentation: F(1, 23) = 39.7, p <.001 Medium effect size: 2 = 0.63 TASK: Managing finances vs. meal preparation The task type was not significant: F(1, 23) = 0.30, p =.58 Small effect size: 2 = 0.013 The interaction of type of task and condition was not significant: F(1, 23) = 0.44, p =.51 Small effect size: 2 = 0.019 Measurement Biases Were the evaluators blind to treatment status? Circle yes or no, and if no, explain. YES/NO One evaluator administered all parts of the evaluation and intervention. Recall or memory bias. Circle yes or no, and if yes, explain. YES/NO Because the objective of the study was to assess recall and memory, this would not be a bias of concern to the researchers. However, a practice effect might bias the results of the study, because it is possible that task recall would improve over each testing period. The researchers accounted for practice effect by reassessing recall and memory after 1 week in both s. 6
Others (list and explain): RESULTS List results of outcomes relevant to answering the focused question Include statistical significance where appropriate (p < 0.05). Include effect size if reported. The results indicate that tasks learned under the generated condition were recalled at a significantly higher rate than the provided condition. The results also indicate that both s (TBI and HC) benefited from the generated condition. Item recall declines were seen in both conditions, but in a similar pattern as time increased from 30 minutes to 1 week. Finally, the results indicate that the task provided did not significantly affect recall. Was this study adequately powered (large enough to show a difference)? Circle yes or no, and if no, explain. YES/NO 15 healthy controls and 10 individuals with TBI were involved. This is not adequately powered; however, the authors identified this as a pilot study, for which it would be appropriate. Were appropriate analytic methods used? Circle yes or no, and if no, explain. YES/NO Were statistics appropriately reported (in written or table format)? Circle yes or no, and if no, explain. YES/NO CONCLUSIONS State the authors conclusions that are applicable to answering the evidence-based question. The researchers intended for this study to be a pilot study to investigate whether self-generated learning using functional tasks compared to a provided condition was effective in individuals with TBI. The intent was to improve on the research base from several successful studies completed with individuals with multiple sclerosis. The results of this study indicate that selfgeneration is potentially effective in both healthy individuals and those with TBI. Additional research is needed in this area for better generalization. References Goverover, Y., Chiaravalloti, N., & DeLuca, J. (2008). Self-generation to improve learning and memory of functional activities in persons with multiple sclerosis: Meal preparation and managing finances. Archives of Physical Medicine and Rehabilitation, 89, 1514 1521. http://dx.doi.org/10.1016/j.apmr.2007.11.059 7
This work is based on the evidence-based literature review completed by Brittany Holmes, BS, MOTS and Karen M. Keptner, MS, OTR/L. Faculty Advisor. Additional input was provided by Leigh Farr, BS, MOTS, and Lindsey Mitchell, BS, MOTS. All authors are affiliated with Cleveland State University in Cleveland, Ohio. CAP Worksheet adapted from Critical Review Form Quantitative Studies. Copyright 1998, by M. Law, D. Stewart, N. Pollack, L. Letts, J. Bosch, & M. Westmorland, McMaster University. Used with permission. For personal or educational use only. All other uses require permission from AOTA. Contact: www.copyright.com 8