Background
Intervention fidelity in CRTs of public health interventions
Framework for the evaluation of implementation fidelity
Fidelity components | |
---|---|
Content | Defined as an attempt to establish the ‘active ingredients’ of the intervention |
Coverage | Refers to the degree to which all persons who met study inclusion criteria received the intervention |
Frequency | Refers to whether the intervention was delivered with the regularity or frequency planned by its designers |
Duration | Establishes whether the intervention was delivered with the duration planned by its designers |
Moderating factors | |
Comprehensiveness of intervention description | Factors such as the degree of intervention complexity and whether the intervention description is complete or incomplete, vague or clear, may influence the degree of intervention fidelity |
Strategies to facilitate implementation | Several support strategies may be used to optimise and to standardise intervention fidelity |
Quality of delivery | Concerns whether an intervention is delivered in a way that increases the likelihood of achieving the desired health outcomes |
Participant responsiveness | Refers to whether researchers established strategies to increase acceptance by and acceptability to those receiving an intervention |
Recruitmenta | Refers to procedures used to attract potential programme participants |
Contexta | Refers to surrounding social systems, such as structures and cultures of organisations and groups, and historical and concurrent activities and events, that may influence study activities |
Fidelity assessment in CRT reporting guidelines
Rationale for undertaking this review
Objective
Methods
Study eligibility
Study designs
Participants
Interventions
Comparators
Outcomes
Report characteristics
Availability of the study protocol
Exclusion criteria
Information sources and search strategy
Study screening and selection
Data extraction and data items
Outcomes and prioritisation
Primary outcome
Protocol | |||
+ | – | ||
Trial Report | + a | b | a + b |
– c | d | c + d | |
a + c | b + d | N |
Secondary outcomes
-
The frequency and proportion of trial protocols reporting assessment of intervention fidelity, out of N
-
The frequency and proportion of trial reports reporting assessment of intervention fidelity, out of N
-
The proportion of positive agreement among those that agree, computed as a/(a+d)
-
Frequency counts and percentages summarising fidelity components examined and data collection methods proposed or employed
Risk of bias in individual studies
Data synthesis
Results
Study selection
Study characteristics
Characteristics | (n) | (%) |
---|---|---|
Study designs | ||
Two-arm parallel cluster randomised trial (CRT) | 49 | 75 |
2 × 2 factorial design CRTs | 9 | 14 |
Three-arm parallel CRTs | 5 | 8 |
Stepped wedge designs | 2 | 3 |
Region | ||
Sub-Saharan Africa | 36 | 55 |
South Asia | 14 | 22 |
Latin America & Caribbean | 6 | 9 |
East Asia & Pacific | 6 | 9 |
Multiple regions | 3 | 5 |
Intervention category | ||
HIV, tuberculosis, malaria, dengue | 24 | 37 |
Child health conditions | 19 | 29 |
Maternal and newborn health | 14 | 22 |
Non-communicable diseases | 8 | 12 |
Comparator (control group) | ||
Receipt of usual services or care | 47 | 72 |
Applied a simplified version of the intervention | 15 | 23 |
Used placebo | 3 | 5 |
Intervention fidelity assessment | ||
Protocol | ||
4 dimensions | 2 | 3 |
3 dimensions | 5 | 8 |
2 dimensions | 11 | 17 |
1 dimension | 18 | 28 |
Not done | 29 | 44 |
Trial | ||
4 dimensions | 5 | 8 |
3 dimensions | 18 | 28 |
2 dimensions | 21 | 32 |
1 dimension | 20 | 31 |
Not done | 1 | 1 |
Outcome
Trial Report | Total | |||
---|---|---|---|---|
Positive | Negative | |||
Trial Protocol | Positive | 35 (a) | 1 (c) | 36 (a + c) |
Negative | 29 (b) | 25 (d) | 54 (b + d) | |
Total | 64 (a + b) | 26 (c + d) | 90 N (a + b + c + d) |
Practices of intervention fidelity assessment in protocols and trial reports
Trial Protocol | |||
---|---|---|---|
Fidelity components | Studies | Study ID | |
(n) | (%) | ||
Content | 34 | 52.3 | [43–76] |
Coverage | 13 | 20 | [43, 44, 50, 53, 57, 62, 64, 69, 73–75, 77, 78] |
Frequency | 12 | 18.5 | [43–45, 49, 50, 52, 57–59, 62, 70, 73] |
Duration | 4 | 6.2 | [50, 63, 70, 73] |
Trial Report | |||
Fidelity components | Studies | Study ID | |
(n) | (%) | ||
Content | 60 | 92.3 | [43–60, 62–69, 71, 73–105] |
Coverage | 34 | 52.3 | [43–48, 50, 52, 53, 57–59, 62–64, 66, 68, 71–75, 77, 80, 84, 85, 90, 93, 94, 97, 98, 101, 103, 105] |
Frequency | 33 | 50.8 | [43–45, 48–50, 52, 57–59, 62, 63, 65, 68–70, 72–74, 78, 80–82, 84, 85, 90, 94, 99, 100, 101, 104–106] |
Duration | 9 | 13.8 | [43, 47, 50, 52, 53, 68, 101, 106, 107] |
Protocol & Trial | |||
Moderating factors | Studies | Study ID | |
(n) | (%) | ||
Comprehensiveness of intervention description | 20 | 30.8 | [43, 48, 50, 52, 55, 59, 62, 63, 66–70, 73, 74, 79, 87, 90, 96, 106] |
Strategies to facilitate implementation | 60 | 92.3 | [43–74, 76–85, 88–93, 95–102, 104–107] |
Quality of delivery | 22 | 33.8 | [43–45, 52, 53, 59, 62–64, 66, 67, 70, 71, 73, 80, 85, 89, 91, 96, 100, 102, 106] |
Participant responsiveness | 37 | 56.9 | [46, 48, 49, 50–53, 55, 57, 58, 62, 64–66, 69, 72–75, 78–81, 84, 87–91, 94, 96, 97, 99, 102, 104, 106, 107] |
Recruitment | 5 | 7.7 | [48, 52, 73, 80, 81] |
Context | 8 | 12.3 | [45, 52, 65, 66, 69, 89, 94, 106] |