| Methods |
Design: three group parallel trial
Purpose: examine the analgesic effect of transcutaneous electrical nerve stimulation (TENS) during colonoscopy |
| Participants |
Patients: out‐patients undergoing colonoscopy
Baseline comparability: yes |
| Interventions |
Placebo: TENS without current
Untreated: no TENS
Experimental: TENS with current
(Co‐intervention: midazoalam, and escape analgesic drugs) |
| Outcomes |
Breakthrough analgesia (mg nalbuphrine)
Patient reported pain (100 point scale)
Endoscopist rated pain (100 point scale)
Post‐procedure evaluation questionnaire (physical discomfort, psychological distress, satisfaction) |
| Notes |
|
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Adequate sequence generation? |
Low risk |
'envelopes shuffled' |
| Allocation concealment? |
Low risk |
'sealed envelopes' |
| Blinding?
Treatment provider |
Unclear risk |
NS |
| Blinding?
Outcome assessor |
Low risk |
'Assesments were conducted by an assistant psychologist (CW) who did not attend the colonoscopy and was blind to study group' |
| Incomplete outcome data addressed?
All outcomes |
High risk |
Drop‐out > 15% or NS |
| Free of selective reporting? |
Unclear risk |
No protocol available |
| Free of other bias? |
Low risk |
|
| No signs of variance inequality or skewness? |
High risk |
Either variance inequality (F‐test statistically significant) or skewness (1.64 standard deviations exceeds the mean) |
| Trial size > 49? |
High risk |
N = 23 |
| Clearly concealed allocation + trial size > 49 + drop‐out max 15% |
High risk |
Trial size < 49 |
