Validation of the Global Treatment Burden Question (GTBQ): A novel single-item measure for use in clinical and research settings

Background A single-item, global measure could be valuable for identifying patients with high treatment burden within clinical practice and research. Aim To validate a novel single-item global measure, named the ‘Global Treatment Burden Question’ (GTBQ). Methods GTBQ: “how hard have you found the work of looking after your health conditions?” (responses “not hard”, “slightly hard”, “moderately hard”, “very hard”, “extremely hard”). Included participants: 18-65 years, ≥2 long-term conditions. Baseline survey: GTBQ, socio-demographics, Multimorbidity Treatment Burden Questionnaire (MTBQ), quality of life, health literacy. Follow-up survey: GTBQ. Electronic health records data: long-term conditions, consultations. Spearman’s Rank correlation (R s ) and intraclass correlation coefficient (ICC) assessed construct validity and test-retest reliability. GTBQ performance was examined against global MTBQ scores to determine optimal thresholds. Results 974 (mean age 51) and 97 participants returned baseline and follow-up surveys, respectively. Responses were positively skewed with 22% reporting no burden at baseline. GTBQ scores were positively associated with global MTBQ scores (R s 0.70); weakly associated with health literacy (R s 0.36) and healthcare use (R s 0.27); and negatively associated with physical health (R s –0.66) and mental health (R s –0.65). ICC was 0.66. GTBQ demonstrated excellent ability to discriminate between high and non-high treatment burden (area under the curve 0.838). Applying a GTBQ threshold of ≥3 yielded specificity 90%, sensitivity 53%, positive-predictive-value 82%, and negative-predictive-value 69%, indicating utility in ‘ruling in’ high treatment burden. Conclusion This novel single-item measure has demonstrated good content and construct validity, moderate test-retest reliability, and strong ability to discriminate between high and non-high treatment burden.