Methodologies used in cost-effectiveness models for evaluating treatments in major depressive disorder: a systematic review

Abstract

BackgroundDecision makers in many jurisdictions use cost-effectiveness estimates as an aid for selecting interventions with an appropriate balance between health benefits and costs. This systematic literature review aims to provide an overview of published cost-effectiveness models in major depressive disorder (MDD) with a focus on the methods employed. Key components of the identified models are discussed and any challenges in developing models are highlighted.MethodsA systematic literature search was performed to identify all primary model-based economic evaluations of MDD interventions indexed in MEDLINE, the Cochrane Library, EMBASE, EconLit, and PsycINFO between January 2000 and May 2010.ResultsA total of 37 studies were included in the review. These studies predominantly evaluated antidepressant medications. The analyses were performed across a broad set of countries. The majority of models were decision-trees; eight were Markov models. Most models had a time horizon of less than 1 year. The majority of analyses took a payer perspective. Clinical input data were obtained from pooled placebo-controlled comparative trials, single head-to-head trials, or meta-analyses. The majority of studies (24 of 37) used treatment success or symptom-free days as main outcomes, 14 studies incorporated health state utilities, and 2 used disability-adjusted life-years. A few models (14 of 37) incorporated probabilities and costs associated with suicide and/or suicide attempts. Two models examined the cost-effectiveness of second-line treatment in patients who had failed to respond to initial therapy. Resource use data used in the models were obtained mostly from expert opinion. All studies, with the exception of one, explored parameter uncertainty.ConclusionsThe review identified several model input data gaps, including utility values in partial responders, efficacy of second-line treatments, and resource utilisation estimates obtained from relevant, high-quality studies. It highlighted the differences in outcome measures among the trials of MDD interventions, which can lead to difficulty in performing indirect comparisons, and the inconsistencies in definitions of health states used in the clinical trials and those used in utility studies. Clinical outcomes contributed to the uncertainty in cost-effectiveness estimates to a greater degree than costs or utility weights.

Better guidelines for better care: accounting for multimorbidity in clinical guidelines – structured examination of exemplar guidelines and health economic modelling

“…212,215,217 The most recent review, by Ali Afzali et al, 218 investigates 14 depression models from the literature and finds evidence of substantial heterogeneity in model structures and types, techniques employed, time horizons and data sources used. The authors identified two key potential problems arising in some of the models reviewed: first, a short time horizon for analysis, particularly where decision trees were employed, which limited the ability of the analysis to capture long-term effects of the interventions (e.g.…”

“…There are some published DES models relevant to depression, but none has included another condition. [211][212][213][214][215] The characteristics of depression alone, and particularly the characteristics of depression alongside another condition, make DES the ideal modelling approach to address the stated research question.…”

“…Consequently Ali Afzali et al 218 proposed to use a DES model with a lifetime horizon, which is in keeping with a growing body of model developers using discrete event models for cost-effectiveness modelling in depression. [212][213][214][215] Key attributes that were identified as being attractive for using a DES model for depression and CHD were the ability to:…”

Evaluating the effectiveness and cost-effectiveness of British Sign Language Improving Access to Psychological Therapies: an exploratory study

“…165 This may be why past economic evaluation modelling studies have focused on shorter time frames. 166 The target population for the economic model was Deaf BSL users with depression and/or anxiety. Originally, it was planned to analyse the diagnosis groups separately (e.g.…”

Cost-effectiveness of depressive episode pharmacological treatment

“…Most of these assessments were recently compared in a well designed systematic review [7]. Multiple treatment meta-analysis reported that one of the selective serotonin reuptake inhibitors [SSRIs] escitalopram, was the most cost-eff ective therapy of depression in primary care settings among the other antidepressants tested [citalopram, duloxetine, fl uoxetine, fl uvoxamine mirtazapine, paroxetine, reboxetine, sertraline and venlafaxine] [8].…”