Table 13.2.b: List of study design features (studies with allocation to interventions at the group level)
|
ClRCT |
ClQ-RCT |
ClNRT |
CITS |
CChBA |
ITS |
ChBA |
EcoXS |
Was there a comparison: |
|
|
|
|
|
|
|
|
Between two or more groups of clusters receiving different interventions? |
Y |
Y |
Y |
Y |
Y |
N |
N |
Y |
Within the same group of clusters over time? |
P |
P |
N |
Y |
N |
Y |
Y |
N |
Were clusters allocated to groups by: |
|
|
|
|
|
|
|
|
Concealed randomization? |
Y |
N |
N |
N |
N |
N |
N |
N |
Quasi-randomization? |
N |
Y |
N |
N |
N |
N |
N |
N |
By other action of researchers? |
N |
N |
Y |
P |
P |
N |
N |
N |
Time differences? |
N |
N |
N |
Y |
Y |
Y |
Y |
N |
Location differences? |
N |
N |
P |
P |
P |
N |
N |
P |
Policy/public health decisions? |
Na |
na |
P |
P |
P |
P |
na |
na |
Cluster preferences? |
Na |
na |
P |
P |
P |
P |
na |
na |
Some other process? (specify) |
|
|
|
|
|
|
|
|
Which parts of the study were prospective: |
|
|
|
|
|
|
|
|
Identification of participating clusters? |
Y |
Y |
Y |
P |
P |
P |
P |
N |
Assessment of baseline and allocation to intervention? |
Y |
Y |
Y |
P |
P |
P |
P |
N |
Assessment of outcomes? |
Y |
Y |
Y |
P |
P |
P |
P |
N |
Generation of hypotheses? |
Y |
Y |
Y |
Y |
Y |
Y |
Y |
P |
On what variables was comparability between groups assessed: |
|
|
|
|
|
|
|
|
Potential confounders? |
P |
P |
P |
P |
P |
P |
P |
P |
Baseline assessment of outcome variables? |
P |
P |
P |
Y |
Y |
Y |
Y |
N |
Note that ‘cluster’ refers to an entity (e.g. an organization), not necessarily to a group of participants; ‘group’ refers to one or more clusters; see Box 13.4.a.
Note that ‘possibly’ is used in the table to indicate cells where either ‘Y’ or ‘N’ may be the case. It should not be used as a response option when applying the checklist; if uncertain, ‘can’t tell’ should be used (see Box 13.4.a).
Y=Yes; P=Possibly; P*=Possible for one group only; N=No; NR=Not required. ClRCT=Cluster randomized controlled trial; ClQ-RCT=Cluster quasi-randomized controlled trial; ClNRT=Cluster non-randomized controlled trial; CITS=Controlled interrupted time series (Shadish 2002); CChBA=Controlled cohort before-and-after study (Shadish 2002); ITS=Interrupted time series; ChBA=Cohort before and after study (Shadish 2002); EcoXS=Ecological cross-sectional study.