Abstract
Background
Commonly used conservative shoulder pain treatments include: advice/analgesia, exercise/manual therapy and, corticosteroid injection. Moderators, patient/clinical attributes influencing treatment effect, facilitate clinical decision-making by identifying which patients might respond best to specific treatments. This review summarises results of studies aiming to identify/test treatment effect moderators.
Methods
Randomised controlled trials (RCTs) containing some form of, or suggested moderation/subgroup analysis (sample size >20, and >10 subjects in smallest subgroup), comparing above treatments against physical/functional/pain outcomes, in adults with shoulder pain were searched for in Medline, Embase, PsychInfo, CINAHL, AMED, Pedro, Cochrane Database. Cochrane Risk of Bias tool and Pincus criteria for moderation analysis were applied.
Results
Six RCTs aiming to identify/test moderators and 16 suggesting potential moderators were included and data narratively synthesised. One trial offered confirmatory level moderation (Pincus criteria). Graded exercise had smaller effect in those with painful arc at baseline, compared against without, although lacked statistical significance (mean difference −14.0 shoulder disability (0–100 scale), 95% CI’s [−28.1, 0.1], p = 0.05). Twenty other factors with insufficient level moderation evidence were identified.
Discussion
Review highlights lack of high-quality evidence for moderators of treatment effect of shoulder pain treatments. Future research should address proposed candidate moderators, using robust moderation methodologies to inform clinical decision-making.
Acknowledgements
The authors thank Dr Miriam Hattle, statistician, for her careful reading and helpful advice when extracting information regarding the statistical analysis (moderation) methods used in each of the trials included in this review.
Disclosure statement
No potential conflict of interest was reported by the author(s).