Reliability, Validity and Effectiveness of Strain Counterstrain Techniques

Abstract

This study examined the reliability and validity of a tender-point palpation scale (TPPS) and the effect of Strain Counterstrain (SCS) on painful tender-points (TP). The experimental design employed a convenience sample of 49 volunteers with bilateral hip TPs, randomly assigned to three groups each receiving SCS, Exercise (EX), or SCS and EX. Pain before and after intervention was assessed with the TPPS and visual analog scale (VAS). Pre-intervention reliability of the TPPS was poor for the hip abductors (kappa = .327) and adductors (kappa = .228). TPPS concurrent validity as compared to VAS was weak (Spearman r=.233 to .709). Even weaker reliability and validity estimates can be assumed for a sample not limited to those with TPs, such as a general clinical population. Interventions were performed twice over two weeks. By study end, all groups demonstrated significant pain decreases in both muscle groups demonstrated with the VAS and TTPS (Wilcoxon: SCS and SCS+EX p<.001; EX p<.01). The SCS groups tended toward greater pain reductions than the EX group for hip abductors and adductors (Kruskal Wallis: VAS p<.05 and p=.06; TPPS p=.09 and p<.001 respectively). However, low TPPS reliability and validity preclude any conclusions based on this assessment method.