| Methods |
Design: three group parallel trial
Purpose: study the effect of TENS during sigmoidoscopy |
| Participants |
Patients: out‐patients needing screening endoscopy
Baseline comparability: yes |
| Interventions |
Placebo: session with TENS machine off
Untreated: no session
Experimental: session with TENS machine turned on
(Co‐intervention: NS) |
| Outcomes |
Pain intensity (1‐5)
Bloating
Nausea
Pain or burning or tingling at electrode site
Pain compared with previous sigmoidoscopy |
| Notes |
|
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Adequate sequence generation? |
Unclear risk |
NS |
| Allocation concealment? |
Unclear risk |
NS |
| Blinding?
Treatment provider |
High risk |
(but endoscopist and patients were blinded) |
| 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? |
Low risk |
|
| No signs of variance inequality or skewness? |
Low risk |
No variance inequality (F‐test not statistically significant) and no skewness (1.64 standard deviations does not exceed the mean) |
| Trial size > 49? |
Low risk |
N = 60 |
| Clearly concealed allocation + trial size > 49 + drop‐out max 15% |
High risk |
Unclear allocation concealment |
