Table 3 Study quality coding criteria

MI development

Evidence-basis and theoretical underpinning of intervention design

Was the multimedia intervention (MI) developed according to cited evidence-based guidelines related to the health condition? And/or was mention made of theoretical constructs used in the development of the MI?

• If either or both of these aspects were mentioned, the quality is coded as YES, otherwise it is coded as NO

• PARTIAL YES (½) is given to interventions that only invite health professionals to be involved in the design and/or development, i.e. no reference to clinical guidelines or theoretical underpinning

Intervention piloting/ testing prior to study commencement

Was the MI piloted during or after the development phase with children of the appropriate age range? Was the MI developed for children of a specified age range, and was it then piloted with this age group prior to undertaking the study?

• The quality is coded as YES if piloting, or iterative child-involvement, has been integral to the MI design and/or development or post-development piloting has taken place that may have led to amendments

• Where piloting or testing has been mentioned, without details about the rigour of the process (such as the ages of the children, the number of children involved, the outcome of the piloting process, etc.), the quality is coded as PARTIAL YES (½)

• The quality is coded as NO if no mention is made of child-involvement during development, piloting or testing

Study design

Appropriately selected age ranges for potential research participants

Did the study include children of an appropriate age range? If the MI was piloted or developed in conjunction with children, are study subjects of a similar age range? Could the MI design be developmentally appropriate for the youngest and the oldest study subjects? In other words, is the age range appropriate or is it too large?

• The quality is coded as YES where the MI has been piloted or tested with children of a similar age to those recruited as study subjects, and the age range is ≤ 7-years

• YES is also given to MIs catering for a wider range of ages, e.g. by way of different levels or difficulties, designed cope with the discrepancies in developmental ability of the children, and study data have been analysed and presented within narrower age ranges

• PARTIAL YES (½) is given to studies where the age range is 7 to 8-years, and the above conditions have not been met

• The quality is coded as NO if piloting of the MI took place with a different age group of children to those recruited to the study, without valid reason or explanation, or the age range of study participants was > 8-years with no stated strategy to deal with differences in developmental abilities

Data collection

Amount of time children viewed the multimedia intervention

How much time did children have to familiarise themselves with the content of the MI? Was the number of sessions reported? Was the length of these sessions stated?

• In order to be coded as YES, the paper must indicate (even if a calculated estimate) the amount of time children spent using the intervention. This may be stated as a total time, or length of time for each session

• A PARTIAL YES (½) is given if the total number of sessions is stated, with no indication of time spent viewing the MI

• The quality is coded as NO if no data, data is unclear, or only partial data is provided (e.g. the length of the first session but not subsequent sessions)