| Methods |
Design: three group, four period cross‐over trial
Purpose: examine the effect of lidocaine patches on post‐herpetic neuralgia |
| Participants |
Patients: out‐patients with post‐herpetic neuralgia
Baseline comparability: not relevant |
| Interventions |
Placebo: patch with vehicle but no lidocaine
Untreated: no patch (observational group)
Experimental: patch with vehicle and lidocaine (two periods)
(Co‐intervention: oral analgesics as prescribed before entering the trial, including escape medication, dose NS) |
| Outcomes |
Pain (VAS)
Side effects
Blood lidocaine |
| Notes |
The outcome data was not available from the first period only, and was calculated as deriving from a parallel group trial. |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Adequate sequence generation? |
Unclear risk |
NS |
| Allocation concealment? |
Unclear risk |
NS |
| Blinding?
Treatment provider |
Low risk |
'... double‐blind controlled study...' |
| Blinding?
Outcome assessor |
Unclear risk |
Not relevant as patient reported outcome |
| Incomplete outcome data addressed?
All outcomes |
Low risk |
Drop‐out < 15% |
| Free of selective reporting? |
Unclear risk |
No protocol available |
| Free of other bias? |
Unclear risk |
The outcome data from this cross‐over trial was not available from the first period only, and was calculated as deriving from a parallel group trial. |
| No signs of variance inequality or skewness? |
Unclear risk |
Not relevant (not naturally positive continuous outcomes e.g. change) |
| Trial size > 49? |
Low risk |
N = 70 |
| Clearly concealed allocation + trial size > 49 + drop‐out max 15% |
High risk |
Allocation not clearly concealed |
