Colonoscopy: more complete examinations and fewer needed further investigations than sigmoidoscopy/enema.

Clinical bottom line (level 1b)

  1. Patients with suspected large bowel disease who had colonoscopy compared with sigmoidoscopy followed by barium enema were more likely to have a complete examination (NNT = 3 at unknown) , and were less likely to require further investigation (NNT = 5 at unknown) .
  2. There was no clear difference in the number of diagnoses made or patient satisfaction with the procedure.
Lindsay et al: British Medical Journal 1988; 296: 167-169
Expires May 2003

The study

Unblinded concealed randomised trial with intention-to-treat
Setting: university hospital, UK

168 patients (aged range 19 to 81 years; mean 56, ?% male) suspected large bowel disease, referred to gastroenterology outpatient clinic
Control Group: (n = 89, 89 analysed): rigid sigmoidoscopy plus barium enema
Experimental Group: (n = 79, 79 analysed): colonoscopy
All patients took sodium picosulphate laxative and oxyphenisatin before the examination.
100% followed for ?
Outcome notes:
  • incomplete examination : examination complete - good views of whole large bowel
  • further investigation required : further investigation required due to poor-quality first investigation

The evidence

Outcome Time to outcome CEREERRRR
(95% CI)		ARR
(95% CI)		NNT
(95% CI)
disease found unknown 31
(34.8%)		 25
(31.7%)		 9%
(-40% to 41%)		 3.19%
(-11.1% to 17.4%)		 31
(NNT = 6 to infinity;
NNH = 9 to infinity)
incomplete examination unknown 57
(64.0%)		 26
(32.9%)		 49%
(27% to 64%)		 31.1%
(16.8% to 45.5%)		 3
(2 to 6)
further investigation required unknown 24
(27.0%)		 6
(7.59%)		 72%
(35% to 88%)		 19.4%
(8.46% to 30.3%)		 5
(3 to 12)
patient would not have investigation again unknown 16
(25.0%)		 19
(29.7%)		 -19%
(-109% to 33%)		 -4.69%
(-20.1% to 10.7%)		 -21
(NNT = 9 to infinity;
NNH = 5 to infinity)

  • Only 64 patients in each group answered the question about undergoing the procedure again.

    • Comments

    1. No long-term follow-up means no comment as to the accuracy of the tests can be made.

    Citation

    1. Lindsay JG, Freeman JG, Cobden I, et al: Should colonoscopy be the first investigation for colonic disease?. British Medical Journal 1988; 296: 167-169
    Search Terms: colit* in Cochrane
    Contributor: Chris Ball and Clare Wotton, November 2000
    Reviewer:

    Clinical Question.
    Patient suspected large bowel disease
    Intervention or Exposure colonoscopy
    Comparison sigmoidoscopy
    Outcome completion of examination, diagnosis of disease