Contingency management for the treatment of marijuana addiction: systematic review and meta-analysis

• Grant number: 20/14540-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2021
• End date: December 31, 2021
• Field of knowledge: Health Sciences - Medicine - Psychiatry
• Principal Investigator: Thiago Marques Fidalgo
• Grantee: Marcelo Gonçalves de Lima
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil

Abstract

Marijuana is the most consumed illicit psychoactive substance worldwide, with a lifetime prevalence of 3.9%. Over the past 20 years, marijuana addiction has consolidated as the third most common in countries like Canada, the United States, and Australia. This position reinforces the necessity to improve treatments for this condition. Contingency Management is a psychosocial intervention created from principles of cognitive-behavioral therapy. It is based on basic operating principles, in which positive behaviors are rewarded. The literature points out that this method is superior to other psychotherapies, but without systematizing the results. Therefore, the objective is to carry out a systematic review with a meta-analysis of controlled and randomized clinical studies (RCT) to assess the effectiveness of contingency management in the treatment of marijuana dependence. Search will be carried out in the following databases: MEDLINE, ClinicalTrials.gov, LILACS, OpenGrey, PycINFO, and EMBASE. The search strategy will use the PICO format (Person, Intervention, Control, Outcome) and will be adapted according to the Boolean operators of each database. The extraction of data from each article will undergo a blind evaluation by two researchers, and the discrepancies will be resolved by consensus. The quality of evidence will be accessed through the GRADE (Grading of Recommendations, Assessment, Development, and Evaluations), the risk of bias will be accessed through the Risk of Bias Assessment tool from the Cochrane Collaboration and the meta-analysis will be performed in the RevMan 5 software. The project was registered on the PROSPERO platform (International Prospective Register of Systematic Reviews).