Determination of the Optimal Cutoff Point for the ChemSex Inventory (CSI) to Assess Chemsex-Related Mental Health Risk in Men Who Have Sex with Men

Background Chemsex poses growing psychological and behavioural risks among men who have sex with men (MSM). Although the Chemsex Inventory (CSI) was developed to assess these risks, clinical cutoff points distinguishing recreational use from pathological patterns remain undefined. This study aimed t...

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Bibliographic Details
Authors: Del Pozo-Herce, P, Martínez-Sabater, A, Chover-Sierra, EE, Czapla, M, Hernado, BS, Navas-Echazarreta, N, Juárez-Vela, R
Format: article
Status:Published version
Publication Date:2026
Country:España
Institution:INCLIVA
Repository:r-INCLIVA. Repositorio Institucional de Producción Científica de INCLIVA
OAI Identifier:oai:dnet:incliva_____::8586d112e456d977cbda184694913ec7
Online Access:https://incliva.portalinvestigacion.com/publicaciones/20814
Access Level:Open access
Keyword:Chemsex
Cutoff scores
Psychometrics
Mental health
Men who have sex with men
Statistical Analysis
Description
Summary:Background Chemsex poses growing psychological and behavioural risks among men who have sex with men (MSM). Although the Chemsex Inventory (CSI) was developed to assess these risks, clinical cutoff points distinguishing recreational use from pathological patterns remain undefined. This study aimed to determine optimal CSI cutoff points to identify profiles of increased psychological and behavioral vulnerability associated with chemsex. Methods A cross-sectional study was conducted in Spain between January and April 2023 with 563 MSM who reported chemsex use within the previous 12 months. Psychometric analyses included principal component analysis (PCA) and confirmatory factor analysis (CFA) of a second-order model with four dimensions: emotional instability, risk of psychosis, altered body perception, and suicide risk. Cutoff points were determined using the percentile-based P-score method. Results The CSI showed excellent internal reliability (Cronbach's alpha = 0.88; omega = 0.88) and strong factorial validity (CFI = 0.985, TLI = 0.984, RMSEA = 0.05). The second-order model fit significantly better than the first-order alternative (chi & sup2;diff = 8.14; p = 0.017). High-risk cutoffs were: emotional instability >= 78.3, psychosis >= 51.4, body-perception disturbance >= 95.0, suicide risk >= 75.0, and global >= 66.4. About 5% of participants exceeded these thresholds, indicating elevated psychological vulnerability. Conclusions CSI cutoff points provide a reliable and sensitive tool for early detection of mental-health risks related to chemsex. Policy Implications Incorporating the CSI into sexual-health, primary-care, and mental-health services may enhance early detection of at-risk individuals and support evidence-based prevention and harm-reduction strategies.