Actual pain ratings were requested for 10 randomly selected trials out of the 36 trials presented in each condition and block.
We assessed the selected trials for quality of trial performance and reporting.
We independently screened the full text articles of selected trials to confirm eligibility and resolved any disagreements by discussion.
Based on previous evidence, we classed the randomisation methods of selected trials as the primary measure of bias control.
To maximise the amount of data, we deliberately considered from the carefully selected trials specific arms of subjects who were eligible, with each group of volunteers acting as his/her own control.
The methodological quality of selected trials assessed by the PEDro scale is shown in Table 1 and a summary of the trials is presented in Table 2. Quality.
A total of 9.5% of the selected trials were excluded from RT analysis: 5.1% because they were excessively slow (>1600 ms) and 4.6% because they resulted in incorrect response.
None of selected trials was a placebo-controlled, double-blind trial.
When the designs of selected trials were unclear in an abstract, we always screened the full-text article.
A summary table was also prepared featuring results of selected trials focusing, again, on vascular dementia (Table 1).
