Table S3. Assessment of bias risk of randomized & controlled clinical trials a
Study
Sequence
Allocation
generation concealment
Blinding of
Incomplete outcome data Free of
participants,
and withdrawals
personnel, and
Other sources of Overall
selective bias and
assessment
reporting? commentaries
High/
outcome assessors
moderate/
low risk of
bias
Deb 1976
No
No
Unclear
No
No
Unclear
No conflict of
Assigned by
“Persons in the
Clinical
strict
placebo group also
outcomes interest was
alternation
received 6 doses of
not
multivitamins to
included
match the dosage
schedule of
tetracycline”.
reported.
High
Echevarria
Yes
Yes
Yes
Unclear
1995
Random
Household contacts
The study drug was 250 were randomized; of
(Main author
table with
enrolled in the study provided in a sachet these, 213 fulfilled all the
Unclear
Unclear
The study was
partially financed
was contacted fixed blocks were given sequential labeled only with the inclusion criteria
by Bayer's Latin
and provided
containing
American Affairs,
further
50 numbers was not possible for Information provided and 17 from the
study numbers. It
study number.
Unclear
(20 from the placebo group
Bayer-México.
information on
either the team
by the author:
ciprofloxacin group were
Conflict of
methods)
members or the
Personnel and
excluded). Two additional
interests not
household contacts
patients were blind;
household contacts were
declared.
to identify the study
the medication and
excluded from the efficacy
Informed Consent,
drugs. Information
placebo had similar
analysis (one voluntarily
protocol approved
provided by the
appearance. Codes withdrew and one was
by Ethical IRB of
author: codes were
were open once the excluded because she
Universidad
assigned centrally.
trial was terminated. received other treatment).
Peruana
Cholera samples were
Cayetano
taken only the 3rd and 7th
Heredia.
days of follow-up.
Joint ICMR-
Unclear
GWB-WHO
1971
Unclear
Unclear
No
No
Unclear
Probably not Probably not done
“In order to avoid
No clinical outcomes were Clinical
done
bias, the study was
collected. No adverse
outcomes interests not
designed as a
events reported. No
not
doubled-blind
baseline characteristics
included
Trial”
reported.
Conflict of
declared.
High
Khan 1982
No
No
No
No
No
Unclear
Assigned by
Half of control group was
No conflict of
strict
not re-visit at 10-12 days
interest was
alternation
Contact participants were
reported.
High
not tested for V. Cholera
Lapeyssonnie Yes
Unclear
Unclear
No
1971
Random
Probably not done
“Double blind”. It is
Only data from contacts
No conflict of
(Preliminary
Table
unclear who was
that were positive to V.
interest was
report. Unclear
blind. No information Cholera the first day was
authorship
relating to whether
No
Unclear
High
reported.
included; data on 30% of
the intended blinding them was not reported. No
No
was effective.
adverse events.
No
Unclear
McCormack
No
1968
Assigned by
Data from 556 data of 655 Clinical
strict
contacts was reported. No outcomes treatment
alternation
information on difference of not
because the
to one of 4
losses according to groups. included
RAMADAN
groups
More families in the groups
dosage schedule
given placebo or one single
was modified.
dose of tetracycline
No conflict of
hydrochloride had at least I
interest was
member (other than the
reported.
index patient) infected
No
Unclear
Differential
High
Sen Gupta
No
No
1978
Unclear
Unclear.
No
Unclear.
Although the term
Of the expected total of
Clinical
No conflict of
“placebo” was used, 2760 samples from 276
outcomes interest was
there is no
contacts, 2672 (96.8 %)
not
reported. The
description that the
were collected.
included
Vibramycin brand
trial was “blind”.
High
of doxycycline
used in the
present trial was
supplied
by the Pfizer
Chemical Co.
a
According to the Cochrane Collaboration Handbook:
Sequence generation: Was the allocation sequence adequately generated?
Allocation concealment: Was allocation adequately concealed?
Blinding of participants, personnel, and outcome assessors: Was knowledge of the allocated intervention adequately prevented during the study?
Incomplete outcome data and withdrawals: Were intention-to-treat analyses performed? Had participants withdrawn from the study?
Free of selective reporting?
Other sources of bias and commentaries: Was sample size calculated? Were inclusion and exclusion criteria and baseline characteristics defined?
Were conflicts of interests reported?
b
Yes = low risk of bias.
c
No = high risk of bias.