Table 4 Applying the iCAT_SR – example A^a

1. Active components included in the intervention, in relation to the comparison

‘Any intervention delivered by LHWs [lay health workers] and intended to improve maternal or child health (MCH) or the management of infectious diseases.’ ([26] p7)

One component

The active component is the delivery by a LHW of a health intervention. Although the nature of the intervention delivered and the extent to which LHWs worked with other providers varied considerably across trials included in the review, all interventions were delivered by LHWs.

2. Behaviour or actions of intervention recipients or participants to which the intervention is directed

‘Any intervention delivered by LHWs and intended to improve maternal or child health (MCH) or the management of infectious diseases…[]…a MCH or infectious diseases intervention was defined as follows.

• Child health: any interventions aimed at improving the health of children aged less than five years.

• Maternal health: any interventions aimed at improving reproductive health, ensuring safe motherhood, or directed at women in their role as carers for children aged less than five years.

• Infectious diseases: any interventions aimed at preventing, diagnosing, or treating communicable diseases…’ ([26] p7-8)

Varied

Included interventions varied from having a single target (e.g., initiation of breastfeeding) to having multiple targets (e.g., community-based interventions directed at hygiene practices, nutrition practices and child caring behaviours among recipients, and intended to reduce neonatal mortality).

3. Organisational levels and categories targeted by the intervention

‘There were no restrictions on the types of patients or recipients for whom data were extracted.’ ([26] p7)

Single category

The interventions delivered by LHWs were directed at individual patients or community members, or groups of patients or community members, within communities or primary care.

4. The degree of tailoring intended or flexibility permitted across sites or individuals in applying or implementing the intervention

‘Any intervention delivered by LHWs and intended to improve maternal or child health (MCH) or the management of infectious diseases.’ ([26] p7)

Varied from inflexible to highly flexible

Because the review included any intervention delivered by LHWs and intended to improve MCH or the management of infectious diseases, the range of included interventions was very wide. Some interventions were implemented in a highly standardised way (e.g., structured telephone support for pregnant women from high risk groups [42]) while others allowed variation from site to side or individual tailoring (e.g., provision of health and parenting education to inner city mothers [43]).

5. The level of skill required by those delivering the intervention in order to meet the intervention objectives

‘Any lay health worker (paid or voluntary) …[]…For the purposes of this review, we defined the term lay health worker as any health worker who:

• performed functions related to healthcare delivery,

• was trained in some way in the context of the intervention, but

• had received no formal professional or paraprofessional

certificate or tertiary education degree.’ ([26] p7)

Mostly varied from basic to intermediate level skills

In the studies included in the review, all of the participating LHWs would have received some level of training. In some studies, LHWs received additional training to extend their skills so that they could deliver a specific task or tasks.

6. The level of skill required for the targeted behaviour when entering the included studies by those receiving the intervention, in order to meet the intervention’s objectives

‘There were no restrictions on the types of patients or recipients for whom data were extracted.’ ([26] p7)

Basic skills

No specialised skills were required of the patients/consumers participating in the trials.

Optional dimension

Description of the intervention in the review

Judgement

Support for judgement

7. The degree of interaction between intervention components, including the independence/interdependence of intervention components

The degree of interaction between intervention components was not specified in the review inclusion criteria, described explicitly in the data extraction or analysed as part of the review. The intervention was considered to have only one component for the purpose of the review.

Unclear or unable to assess

Not described or analysed in the review. Likely to vary across the included studies.

8. The degree to which the effects of the intervention are dependent on the context or setting in which it is implemented

‘A substantial proportion of the included studies…were conducted in LMICs [low and middle income countries] or were directed at low income groups in high income countries. Based on the premise that low income groups across different countries share similar constraints in accessing health care, it may be concluded that these interventions could potentially be extrapolated to other settings, be effective in reaching low income groups, and contribute to reducing health inequalities. However, the degree to which the findings from studies in high income settings can be generalised to low income settings remains unclear and requires further empirical research.’ ([26] p49)

‘While we explored whether there were differences between high, middle and low income countries in the barriers and facilitators we identified, the differences we did find were perhaps surprisingly few…[]… Some differences between settings did emerge, however.’ ([25] p39)

Moderately to highly context dependent

The effectiveness review did not address this question but identified it as important to consider in future work. The qualitative evidence synthesis noted that descriptions of study context were limited. The broad categories of high, middle and low income country did not appear to be key in terms of context dependency, but the synthesis identified a wide range of other ways in which the effects of LHW programmes may be dependent on implementation context or setting.

9. The degree to which the effects of the intervention are changed by recipient or provider factors

Not considered in detail in the reviews.

Moderately to highly dependent on individual-level factors

Many LHW interventions are intended to change the behaviour or recipients (e.g. to increase breastfeeding or promote adherence to a treatment). We would therefore expect these interventions to be dependent on recipients’ readiness for behaviour change, their self-efficacy and the social support that they receive.

10. The nature of the causal pathway between the intervention and the outcome it is intended to effect

‘…the findings of the qualitative review were organised into chains of events that we proposed could lead to the outcomes measured in the review of effectiveness…’ ([25] p35).

Pathway variable, long

More than one causal pathway was identified and each pathway included three or more steps between intervention and outcome.