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Brief Assessment Instruments. William P. Wattles, Ph.D. Francis Marion University. Brief therapy and assessment. Managed Care emphasizes: Cost containment Documented treatment efficacy. Assessment. A full test battery is not longer an option for most practitioners.
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Brief Assessment Instruments William P. Wattles, Ph.D. Francis Marion University
Brief therapy and assessment • Managed Care emphasizes: • Cost containment • Documented treatment efficacy
Assessment • A full test battery is not longer an option for most practitioners. • Psychologists’ biggest challenge is demonstrating the financial efficacy of their services.
3 Brief Instruments • Treatment planning • Outcome assessment • Monitoring
Brief Instruments • Brief Symptom Inventory (BSI) • Beck Depression Inventory (BDI) • State Trait Anxiety Inventory (STAI)
Brief Instruments • Good reliability • Adequate validity • Good relevancy
Beck Depression Inventory William P. Wattles, Ph.D. Francis Marion University
Measures self-reported depression • Response bias may lead some to exaggerate or minimize (or deny) symptoms. • Diagnosis of depression requires examination by a clinician.
Beck Depression Inventory -II • 21-item self-report instrument • Measures severity of depression in adults and adolescents 13 and older • Corresponds to criteria in DSM-IV
History • Created in 1961 • Revised in 1996 after 35 years • Based on descriptive statements reported by psychiatric patients who were depressed but not by other psychiatric patients • Resulted in 21 items • Original version read by trained observer
Mood Pessimism Sense of Failure Self-dissatisfaction Guilt Punishment Self-Dislike Self-Accusations Suicidal Ideas Crying Irritability Social Withdrawal Indecisiveness Body Image change Work Difficulty Insomnia 21 Items
Fatigability Loss of Appetite Weight Loss Somatic Preoccupation Loss of Libido 21 Items (cont)
Items dropped Body Image change Work difficulty Weight loss Somatic preoccupation Items added Agitation Worthlessness Loss of energy Concentration difficulty Revision
Old item insomnia loss of appetite Loss of libido Fatigability New Item changes in sleeping pattern changes in appetite loss of interest in sex tiredness or fatigue Items changed
Critical items • “The clinician should pay special attention to the responses to item 2 (pessimism) and Item 9 (suicidal thoughts or wishes) as indicators of possible suicide risk
Administration • Time: 5-10 minutes to complete • Answers should be for the past two weeks • extended from one week for DSM-IV • Check to be sure that all items have been completed
Scoring • Each item is rated 0 - 3 • If more than one is selected choose the higher figure • Scores can range from 0 to 63
Interpreting Scores • Choice of cut scores depends on purpose for using the test.
Sensitivity-the probability of correctly classifying a respondent as depressed. • Specificity-the probability of correctly classifying a respondent as not depressed
Simple thinking Not depressed depressed frequency Number of symptoms
Criterion Simple thinking Not depressed depressed frequency Number of symptoms
Not depressed depressed Reality frequency Number of symptoms
Not depressed depressed frequency Criterion Number of symptoms
Correct reject False alarm frequency Number of symptoms
Miss Hit frequency Criterion Number of symptoms
Hits 97.5%84%50% False Alarms84%50%16% frequency Number of symptoms
Not depressed depressed frequency Criterion Number of symptoms
ROC Curves • Receiver-operating characteristic curves capture in a single graph the various alternatives as you move the criterion to higher or lower levels. • False alarm rate on the X (horizontal) axis • Hit rate on the Y (vertical) axis
ROC Curves • the area under the ROC (AUR) curves for the BDI–II was .78 (95% CI, .68 to .86) • The AUR is an overall index of the accuracy of discrimination provided by a scale, and an AUR of .50 represents chance discrimination.. • A BDI–II total cutoff score of 24 and above had the highest clinical efficiency (72%) with a sensitivity rate of 74% and a specificity rate of 70%
Hits ROC Curves False Alarms
Cut score threshold • If purpose is to detect the maximum number of persons with depression the cut score threshold should be lowered. • For research where it is important to obtain a “pure” group, cut score should be raised to minimize false positives.
Psychometric characteristics • Outpatient samples from four outpatient clinics • 277( 55%) Cherry Hill, New Jersey • 50 (10%) Bala Cynwyd, Pennsylvania • 127 (25%) Philadelphia, Pennsylvania • 46 (9%) Louisville, Kentucky
Gender Women 63% Men 37% Race White 91% Black 4% Asian America 4% Hispanic 1% Disorder mood dis. 53% anxiety dis 18% adjustment dis 16% other dis 14% Sample characteristics
Depression Ratings • All patients were diagnosed by experienced psychologists or psychiatrists according to DSM criteria • Patient participation was voluntary with informed consent.
Student Sample • 120 intro psych students • women 67% • men 44% • Predominately white • mean age 19.6 (SD=1.84)
Reliability • Internal Consistency • Coefficient Alpha • outpatients .92 • students .93 • All items correlated significantly with the total score. • outpatients ranging from .39 (Loss of interest in sex) to .70 (loss of pleasure) • students ranging from .27 (Loss of interest in sex) to .74 (self-dislike) .
Reliability • Test-retest stability • 26 Philadelphia outpatients administered BDI-II a week apart. • Test-retest r= .93
Validity • Content validity-the construction process consisted of 21 areas that differentiated depressed from non-depressed patients. • Content validity- BDI-II reworded and added to assess DSM-IV criteria for depression.
Validity • Construct validity • Correlation with original BDI r=.93 • Mean score 2.96 points greater than original BDI
Validity • Convergent validity • correlates with Beck Hopelessness Scale • r=.68 • correlates with Scale of suicide ideation • r=.37 • Hamilton Psychiatric Rating scale for depression • r=.71 • Discriminate Validity-not measured
Validity • The Beck Depression Inventory-II and the Reynolds Adolescent Depression Scale (RADS; Reynolds, 1987) were administered to 56 female and 44 male psychiatric inpatients whose ages ranged from 12 to 17 years old. • The Cronbach coefficient alpha(s) for the BDI-II and RADS were, respectively, .92 and .91 and indicated comparably high levels of internal consistency. • The correlation between the BDI-II and RADS total scores was .84,p <.001.
Item-option characteristic curves • Each item demonstrates increasing monotonic relationship with self-reported depression • Items 6, 9, 11, 21 show variation in rank of items selected • patients with sever depression unlikely to acknowledge suicidal intent
Factorial Validity • Identified two factors • Somatic Affective • loss of pleasure, crying, agitation, loss of interest, indecisiveness, loss of energy, changes in sleep, irritability, changes in appetite, concentration difficulty, tiredness. • Cognitive • sadness, pessimism, past failure, guilty feelings, punishment, self-dislike, self-criticalness, suicidal thoughts, worthlessness
Race and Gender • No differences found between white and non-white scores • Women scored higher than men: • Men Mean= 20.44 (SD=13.28) • Women Mean=23.61 (SD=12.1)
Sleeping and eating • Changes in sleeping pattern • 30% sleeping more • 50% sleeping less • Changes in eating • 39% decreased appetite • 20% increased appetite