An exercise in cost-effectiveness analysis: treating emotional distress in melanoma patients Bares C B, Trask P C, Schwartz S M

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1 An exercise in cost-effectiveness analysis: treating emotional distress in melanoma patients Bares C B, Trask P C, Schwartz S M Record Status This is a critical abstract of an economic evaluation that meets the criteria for inclusion on NHS EED. Each abstract contains a brief summary of the methods, the results and conclusions followed by a detailed critical assessment on the reliability of the study and the conclusions drawn. Health technology The use of standard care versus standard care plus cognitive-behavioural therapy (CBT) for the treatment of melanoma patients with emotional distress. Standard care consisted of an initial appointment, surgery, and a follow-up appointment to determine the need for additional therapy for the melanoma. Mental health services were available on an as-needed basis. In addition, staff gave reassurance via distress-driven telephone calls beyond what would usually be required for dealing with their physical illness. CBT involved standard care and the provision of four sessions of individual therapy to highly distressed melanoma patients by a staff level, licensed, clinical psychologist. Type of intervention Treatment. Economic study type Cost-effectiveness analysis. Study population The study population comprised melanoma patients who were considered to be suffering from psychological issues, emotional distress and treatment-seeking-related distress. The participants were assessed for levels of distress, coping styles, anxiety levels and health functioning on four different occasions. Those with moderate to high levels of distress (Global Severity Index, GSI, Area T scores of at least 60) were included. Setting The setting was tertiary care. The economic analysis was carried out in Michigan, USA. Dates to which data relate The dates to which the effectiveness evidence, resources and prices related, were not reported. Source of effectiveness data The evidence for the final outcomes was derived from a single study. Link between effectiveness and cost data The costing was undertaken retrospectively using the same sample of patients as that used in the effectiveness study. Study sample There was no mention of using power calculations to determine the sample size. The total sample comprised 38 patients who were enrolled in an internally funded longitudinal study at the Multidisciplinary Melanoma Clinic. Of the 38 patients enrolled, 19 patients were randomised to standard care and 19 to standard care plus CBT. Of those randomised Page: 1 / 5

2 to CBT, 8 declined post-randomisation to engage in treatment. Study design The study was a randomised controlled trial (RCT) that was conducted in a single centre (the Multidisciplinary Melanoma Clinic). The participating patients were assessed before the initial appointment and at 2, 5 and 9 months after the initial appointment. The authors did not conduct this study. They retrospectively used the effectiveness results obtained. Analysis of effectiveness The basis of the analysis of the clinical trial was reported to be an active treatment approach, which implies that it was treatment completers only. The primary health outcome was the distress level of the patients in each condition. The overall measure of patient distress was the GSI of the Brief Symptom Inventory. The initial distress levels were not significantly different between the two groups. No further details were provided on the comparability of the groups at baseline. Effectiveness results The mean level of distress at the 2-month assessment was for the standard care group and for the standard care plus CBT group. These levels were clinically elevated, but were not statistically different, (t(28)=0.212, p=0.833). The mean levels for the standard care group had not changed much at 5 months (64.27). This change was not statistically significant, (t(14)=0.966, p=0.350). However, the CBT group reported an average distress level within the normal range of This change was both clinically and statistically significant, (t(10)=3.619, p<0.005). Clinical conclusions The authors concluded that the statistically significant change in distress levels of the standard care plus CBT group supported their first hypothesis that patients would benefit from CBT relative to standard care in terms of decreased levels of distress. Methods used to derive estimates of effectiveness The authors made one major assumption. Estimates of effectiveness and key assumptions It was assumed that the psychological intervention would completely reduce the occurrence of the illness behaviour. Measure of benefits used in the economic analysis The main outcome measure was the reduction of the mean distress levels. A normal level of distress level was defined as a score of at least 60 on the GSI. Direct costs The costs were incurred during less than one year, therefore discounting was, appropriately, not carried out. The costs and the quantities were reported separately. The quantities and costs were estimated from actual data. The cost boundary adopted was that of the health service provider. The quantity data were derived from the diary estimates of phone contacts obtained from the individuals over a 1-week period. The nurses' estimates revealed that they spent an additional 3.75 hours/week and physicians an additional 1.63 hours/week talking with distressed patients. The staffing costs were based on salary information provided by the department's financial analyst (MD salary $60K per year and RN salary $45K per year). The other costs considered were staffing costs for the scheduling and creation of workbooks. These were based on a clinical psychology postdoctoral fellow salary of $28K. Page: 2 / 5

3 Statistical analysis of costs The costs were not treated stochastically. Indirect Costs The indirect costs were not considered since the study was conducted from a provider perspective. Currency US dollars ($). Sensitivity analysis A sensitivity analysis was not undertaken. Estimated benefits used in the economic analysis The estimated benefit used was the difference in distress levels before and after each intervention. Cost results The cost of addressing emotional distress was $0.41 per minute for standard care and $0.49 per minute for CBT. The total cost was $358 for providing standard care and $98.16 for providing standard care plus CBT. A further analysis considered the profit calculations if the cognitive-behavioural intervention was reimbursed. This indicated that the CBT group would generate $1.16 of revenue per minute provided that the intervention was part of standard care to melanoma patients, whereas the standard care group would generate $0.41 per minute without apparent clinical benefit. Synthesis of costs and benefits The costs and benefits were combined by first calculating the difference in distress levels at 2 and 5 months. The costeffectiveness ratio was then calculated by dividing the total cost of each condition by the change in distress level. The cost effectiveness ratio was $ for standard care and $7.66 for standard care plus CBT. Authors' conclusions Although the per minute cost of providing the psychological intervention was marginally greater than standard care, providing the intervention was significantly cheaper in terms of stress reduction. CRD COMMENTARY - Selection of comparators The comparator was justified on the grounds that evidence existed of potential benefits when behavioural interventions were applied to medically ill populations. You should decide whether this is a widely used health technology in your own setting. Validity of estimate of measure of effectiveness The study used a retrospective analysis of a RCT. The authors acknowledged that a prospective RCT would have been more appropriate for the study question. The reporting of the original RCT was very limited and, although the study sample appears to have been representative of the study population, it was difficult to be sure. In addition, there were insufficient details of the comparability of the two groups at baseline. Power calculations were not reported and, given the small sample size, it is likely that they were not conducted. It is possible that biases and confounding factors could Page: 3 / 5

4 be present, even though the original study was a RCT. The outcomes were analysed for treatment completers only. However, an intention to treat analysis would have increased the generalisability of the results to a real life setting. It was difficult to ascertain the internal validity of the study due to the limited reporting. Validity of estimate of measure of benefit The estimate of benefit was obtained directly from the effectiveness analysis. The authors justified their choice of estimate. Validity of estimate of costs All the categories of costs relevant to the perspective adopted were included in the analysis. The costs and the quantities were reported separately, which will aid the interpretation of the results in different settings. No statistical analysis of the quantities or costs was performed. The sources used to obtain the cost data were not reported. Median salary values were used to calculate the per minute cost of engaging in each task. The price year was not reported. Other issues The authors made appropriate comparisons of their results with findings from other studies, but they did not address the issue of generalisability to other settings. The authors do not appear to have presented their findings selectively. The conclusions reflected the scope of the analysis, as the economic analysis was carried out retrospectively. The authors reported further limitations to their study. First, the study was not designed as an economic evaluation and, therefore, the methodological rigour necessary for prospective cost effectiveness was lacking. Second, the study used estimates to calculate the cost and effectiveness of standard care. The authors indicated that, to effectively deal with this issue, future studies would need to have a priori identification of the costs to be measured and accurately monitor the costs associated with each intervention. Finally, in order to better quantify the economic impact, it was assumed that the successful reduction of emotional distress would eliminate entirely the distress-driven illness behaviour. Implications of the study The authors indicated that their results illustrate the potential clinical and economic benefit of incorporating effective psychological and behavioural interventions into standard medical care for risk patients. The limitations of the study highlighted the need for further research into this area. Source of funding None stated. Bibliographic details Bares C B, Trask P C, Schwartz S M. An exercise in cost-effectiveness analysis: treating emotional distress in melanoma patients. Journal of Clinical Psychology in Medical Settings 2002; 9(3): Indexing Status Subject indexing assigned by CRD MeSH Anxiety; Cognitive Therapy /economics; Comparative Study; Cost-Benefit Analysis; Depression /therapy; Emotions; Female; Health Status; Humans; Male; Melanoma /psychology; Psychometrics; Quality of Life; Surveys and Questionnaires; Skin Neoplasms /psychology; Stress, Psychological /therapy AccessionNumber Date bibliographic record published Page: 4 / 5

5 Powered by TCPDF ( 29/02/2004 Date abstract record published 29/02/2004 Page: 5 / 5