| |
Earlier
we introduced levels of measurement and emphasized that the decision
to measure a variable in a particular way not only directs our
subsequent analytic (i.e. statistical) options but also influences
the general appearance of our research design. Efforts to judge
the quality of research -- i.e. both its internal and external
validity -- turn mostly on unbiased review of the stream of interconnectedness,
or integration, between the research question, the project design,
the analytic approach, and our conclusions. The links between
these primary aspects of clinical investigations are explicit,
for example, in the checklist of items included for improving
the reporting of randomized clinical trials (Moher
et al., 2001). Review the following Table from the 2001 CONSORT
statement, and count the number of items you think are related
either implicitly or explicitly to measurement:
| Table
26.1: Checklist of Items to Include when Reporting a
Randomized Clinical Trial
|
|---|
| Section
and Topic
| Item
#
| Descriptor
|
|---|
| Title
and Abstract
|
1
|
How participants were allocated to interventions (e.g.
"random allocation," "randomized,"
or "randomly assigend")
|
|---|
| Introduction
|
|---|
|
Background
|
2
|
Scientific
background and explanation of rationale
|
| Methods
|
|---|
| Participants |
3
|
Eligibility
criteria for participants and the settings and locations
where the data were collected
|
| Interventions |
4
|
Precise
details of the interventions intended for each group
and how and when they were actually administered
|
| Objectives |
5
|
Specific
objectives and hypotheses
|
|
Outcomes |
6
|
Clearly
defined primary and secondary outcome measures and,
when applicable, any methods used to enhance the quality
of measurements (e.g. multiple observations, training
of assessors)
|
|
Sample size |
7
|
How
sample size was determined and, when applicable, explanation
of any interim analyses and stopping rules
|
| Randomization |
Sequence generation |
8
|
Method
used to generate the random allocation sequence, including
details of any restriction (e.g. blocking, stratification)
|
|
Allocation concealment |
9
|
Method
used to implement the random allocation sequence (e.g.
numbered containers or central telephone), clarifying
whether the sequence was concealed until interventions
were assigned
|
|
Implementation |
10
|
Who
generated the allocation sequence, who enrolled participants,
and who assigned participants to their groups
|
|
Blinding (masking) |
11
|
Whether
or not participants, those administering the interventions,
and those assessing the outcomes were blinded to group
assignment. If done, how the success of blinding was
evaluated
|
|
Statistical methods |
12
|
Statistical
methods used to compare groups for primary outcome(s);
methods for additional analyses, such as subgroup
analyses and adjusted analyses
|
| Results
|
|---|
| Participant
flow |
13
|
Flow
of participants through each stage (a diagram is strongly
recommended). Specifically, for each group report
the numbers of participants randomly assigned, receiving
intended treatment, completing the study protocol,
and analyzed for the primary outcome. Describe protocol
deviations from study as planned, together with reasons.
|
|
Recruitment |
14
|
Dates
defining the periods of recruitment and follow-up
|
| Baseline
data |
15
| Baseline
demographic and clinical characteristics of each group |
| Numbers
analyzed |
16
| Number
of participants (denominator) in each group included
in each analysis and whether the analysis was by "intention-to-treat."
State the results in absolute numbers when feasible
(e.g. 10/20, not 50%) |
| Outcomes
and estimation |
17
| For
each primary and secondary outcome, a summary of results
for each group, and the estimated effect size and its
precision (e.g. 95% confidence interval) |
| Ancillary
analyses |
18
| Address
multiplicity by reporting any other analyses performed,
including subgroup analyses and adjusted analyses, indicating
those prespecified and those exploratory. |
| Adverse
events |
19
| All
important adverse events or side effects in each intervention
group |
| Comment
|
|---|
| Interpretation
|
20
| Intrepretation
of the results, taking into account study hypotheses,
sources of potential bias or imprecision, and the dangers
associated with multiplicity of analyses and outcomes |
| Genrealizability |
21
| Generalizability
(external validity) of the trial findings |
| Overall
evidence |
22
| General
interpretation of the results in the context of current
evidence |
|
Question
26.1
How many of the 22
items on the CONSORT checklist relate either implicitly or explicitly
to measurement:
 | At
least 5 |
 | At
least 10 |
 | At
least 15 |
 | At
least 20 |
|