showing only those variables that were identified as significant (p < 0.05) in univariate regression for PRISMA scores and the results of subsequent input to multiple regression, again showing only significant results.

The overall model fit for final multiple regression equation was R2 = 0.29. N.B. Change in PRISMA score refers to the expected change in PRISMA score with a unit increase in the variable assessed with all other variables being constant. NB. systematic review (SR); meta-analysis (MA); confidence interval (CI).