Methodological Considerations in Social Cost Studies of Addictive Substances: A Systematic Literature Review

Effectiveness of Remote Intensive Counseling Versus Outpatient Counseling in Substance Use Disorders: A Retrospective Cohort Study

Background

Substance use disorders are a serious and persistent U.S. public health problem. Although a number of therapy modalities exist, few studies assessed the comparative effectiveness of specific therapies. This study empirically evaluated whether remote intensive counseling (RIC) is more effective than outpatient therapy (OT) in relapse prevention over the period of nine months in patients aged 18-45 years with a history of substance use.

Methods

The current study utilized a retrospective correlational cross-sectional cohort quantitative research design with multiple between-group comparisons and fixed effects. The sample (n=296) included adults of both sexes, of diverse racial/ethnic backgrounds, and of socioeconomic status (SES) between 18-45 years of age who had been using an illicit addictive substance(s) for at least six months prior and had never participated in any treatment program previously. Individuals with alcohol and/or nicotine co-dependence were excluded.

Result and conclusion

Remote intensive counseling (RIC) is more effective for patients aged 18-45 years with a history of substance use than outpatient therapy (OT). RIC works better for single or never married females younger than 30-year-old with higher education. The use of RIC for other age and racial/ethnic groups should be guided by whether patients belong to a younger age cohort and/or a specific race/ethnicity.

Willingness to pay vs lottery equivalent to value the impact of alcohol misuse on quality of life

OBJECTIVES

To estimate the impact of alcohol disorders using lottery equivalent (LE) and willingness to pay (WTP) methods and compute the WTP for a QALY (WTP-Q) derived from these values.

METHODS

Two samples of 300 people valued nine states of alcohol misuse. LE and WTP were used in sample 1 and 2, respectively. The ability to discriminate between methods was tested. Regression models were performed to estimate the preference weights of dimensions. Several values of WTP-Q were obtained by combining the estimated values from both samples.

RESULTS

LE and WTP produce the same ranking of states but LE is more sensitive. The estimated impact of the nine states ranges between 0.91 and 0.22 QALYs, and the WTP for avoiding them ranges between €10,444 and €4132. WTP-Q varies between €11,473 and €19,092 when the mean values of the states are used. The WTP-Q tends to decrease with the severity.

CONCLUSIONS

Although LE and WTP provide values for cost-utility and cost-benefit analyses, respectively, LE seems to be preferable for measuring the impact of alcohol disorders. As the lower sensitivity of WTP seems to explain a WTP-Q decrease with severity, more research is needed before recommending the use of different WTP-Q values.

Methodological considerations in the assessment of direct and indirect costs of back pain: A systematic scoping review

Background

Back pain is a common and costly health problem worldwide. There is yet a lack of consistent methodologies to estimate the economic burden of back pain to society.

Objective

To systematically evaluate the methodologies used in the published cost of illness (COI) literature for estimating the direct and indirect costs attributed to back pain, and to present a summary of the estimated cost burden.

Methods

Six electronic databases were searched to identify COI studies of back pain published in English up to February 2021. A total of 1,588 abstracts were screened, and 55 full-text studies were subsequently reviewed. After applying the inclusion criteria, 45 studies pertaining to the direct and indirect costs of back pain were analysed.

Results

The studies reported data on 15 industrialised countries. The national cost estimates of back pain in 2015 USD ranged from $259 million ($29.1 per capita) in Sweden to $71.6 billion ($868.4 per capita) in Germany. There was high heterogeneity among the studies in terms of the methodologies used for analysis and the resulting costs reported. Most of the studies assessed costs from a societal perspective (n = 29). The magnitude and accuracy of the reported costs were influenced by the case definition of back pain, the source of data used, the cost components included and the analysis method. Among the studies that provided both direct and indirect cost estimates (n = 15), indirect costs resulting from lost or reduced work productivity far outweighed the direct costs.

Conclusion

Back pain imposes substantial economic burden on society. This review demonstrated that existing published COI studies of back pain used heterogeneous approaches reflecting a lack of consensus on methodology. A standardised methodological approach is required to increase credibility of the findings of COI studies and improve comparison of estimates across studies.

Measuring intangible cost-of-morbidity due to substance dependence: implications of using alternative preference-based instruments

OBJECTIVE

Drug and/or alcohol dependence (DAD) generates substantial costs to society. One of the main consequences of DAD is its negative impact on health-related quality of life (HRQoL). The main objective of this study is to analyse the impact of using EQ-5D-5L, SF-6D_SG (SF-6D using standard-gamble as the preference-eliciting method) and SF-6D_PG (SF-6D using a paired-gamble method), to estimate the HRQoL burden, attributable to DAD, within the cost-of-illness framework.

METHODS

A convenience sample of 109 patients with a diagnosis of substance use disorder was recruited. SF-6D and EQ-5D-5L were administered and then the utility scores were computed. The impact of employing different instruments to estimate the HRQoL burden was assessed by comparing the utility scores of patients and general population after controlling for sex and age through regression analysis. The analysis was reproduced for two subgroups of severity.

RESULTS

All instruments detect that DAD significantly affects the HRQoL. However, the estimated impact changes, according to the instrument used, whose pattern varies by severity group. Nonetheless, regardless of severity, SF-6D_PG always estimates a higher or equal DAD burden than the other instruments considered. These results are compatible with the presence of the floor effect in SF-6D_SG, the ceiling effect in EQ-ED-5L, and a smaller presence of both biases in SF-6D_PG.

CONCLUSIONS

The SF-6D_PG instrument emerges as a good candidate to avoid under-estimating intangible costs within the cost-of-illness framework. However, further research is needed to assess the validity of our results in the context of other health problems.