Trial participants were mainly male, except in trials including rotator cuff tears, and elbow and Achilles tendinopathies. Three trials were judged as being at APR-246 mw low risk of bias; the other 16 were at high or unclear risk of bias relating to selection, detection, attrition or selective reporting, or combinations of these. The methods of preparing platelet-rich plasma (PRP) varied and lacked standardisation and quantification of the PRP applied to the patient. We were able to pool data for our primary outcomes (function, pain, adverse events) for a maximum of 11 trials and 45% of participants. The evidence for all primary outcomes

was judged as being of very low quality. Data assessing function in the short term(up to three months) were pooled from four trials that assessed PRT in three clinical conditions and used four different measures. These showed no significant difference

between PRT and control (SMD 0.26; 95% confidence interval (CI) -0.19 to 0.71; P value 0.26; I-2 = 51%; 162 participants; positive values favour PRT). Medium-term function data (at six months) were pooled from five trials that assessed PRT in five clinical conditions and used five different measures. These also showed no difference between groups (SMD -0.09, 95% CI -0.56 to 0.39; P value 0.72; I-2 = 50%; 151 participants). Long-term function data (at one AZD8186 cost year) were pooled from 10 trials that assessed PRT in five clinical conditions and used six different measures. These also showed no difference between groups (SMD 0.25, 95% CI -0.07 to 0.57; P value 0.12; I-2 = 66%; 484 participants). Although the 95% confidence intervals indicate the possibility of a poorer outcome in the PRT group up to a moderate difference in favour of PRT at short-and long-term follow-up, these do not translate into clinically relevant

differences. Data pooled from four trials that assessed PRT in three clinical conditions showed a small buy C188-9 reduction in short-term pain in favour of PRT on a 10-point scale (MD -0.95, 95% CI -1.41 to -0.48; I-2 = 0%; 175 participants). The clinical significance of this result is marginal. Four trials reported adverse events; another seven trials reported an absence of adverse events. There was no difference between treatment groups in the numbers of participants with adverse effects (7/241 versus 5/245; RR 1.31, 95% CI 0.48 to 3.59; I-2 = 0%; 486 participants). In terms of individual conditions, we pooled heterogeneous data for long-term function from six trials of PRT application during rotator cuff tear surgery. This showed no statistically or clinically significant differences between the two groups (324 participants). The available evidence is insufficient to indicate whether the effects of PRT will differ importantly in individual clinical conditions.