Horner 2015.

Methods	Included as outcome evaluation and process evaluation Intervention study design: cluster parallel‐group design, with schools selected as unit of randomisation, using a stratified design according to school characteristics Setting: 33 elementary schools in 5 rural Texas, USA, districts participated in the study Period: dates on which study was conducted ‐ intervention and subsequent data collection ‐ not clear; data were collected over a 12‐month period
Participants	Eligible sample frame: a total of 292 children were enrolled Randomised: a total of 292 children were enrolled and were randomised to 1 of 3 groups; information from 2 groups of interest provided here. 96 children were randomised to the school‐based intervention group and 100 children to the attention control group Completed (intervention): 84 children completed the intervention and attention control Inclusion criteria: children were eligible if they had doctor‐diagnosed asthma, had experienced asthma symptoms in the previous 12 months, and could speak either English or Spanish Exclusion criteria: no significant comorbidity that would preclude participation in classes Baseline characteristics Age of children (based on completers): mean age, 8.8 years Ethnicity (based on completers): treatment: 22.9% white, 55.2% Hispanic, 21.9% African American; control: 11.3% white, 60.8% Hispanic, 27.8% African American Socio‐economic status (based on completers): 31.2% defined as lower SES group in intervention group and 29.8% in control group Gender (based on completers): treatment: 55.2% male, 44.6% female; control: 76.0% male, 24.0% female Asthma status: mixed levels of asthma severity; similar levels between treatment and control groups when measured on the Severity of Chronic Asthma Scale
Interventions	Intervention: the "Asthma Plan for Kids" curriculum, specifically designed for children in rural areas, was provided to the intervention group as group instruction. Topics within the curriculum included: "(1) identifying lung function, asthma warning signs, symptoms, and triggers; (2) learning skills to manage symptoms, including peak expiratory flow score interpretation, communication with adults, medication use, and inhaler technique; (3) evaluating asthma symptoms and the effectiveness of management; and (4) discussing how to safely keep active during physical activity and sports" Control: an equivalent attention control was provided. This mirrored the structure of the school‐based intervention but differed in providing a non‐asthma‐based curriculum. The content consisted of topics on general health information identified by school nurses as useful, including handwashing, nutrition, brushing teeth, and exercising Intensity: 15‐minute lessons spread over 16 sessions that took place within a 5‐week period Instructor: trained lay health educators Theoretical framework: Bruhn's theoretical model of asthma self‐management Parental engagement: not reported Child satisfaction: not reported Timing: sessions held during lunchtime (15‐minute blocks)
Outcomes	Quantitative outcomes Extractable outcomes were collected for: Exacerbations leading to hospital admission Asthma symptoms leading to emergency hospital visits Withdrawal Core processes evaluated (child level): attrition, adherence
Notes	This study compared the treatment (a school‐based intervention) group vs an attention control group; also compared the school‐based intervention vs the same intervention provided at an asthma day camp (although these data are not extracted here) Data were collected on office visits, but unclear whether office visits were restricted to community primary care providers or included specialist consultations Additional measures of process evaluation quality Process evaluation category: integrated within outcome evaluation Breadth and depth: neither broad nor deep Voice of children given prominence: featured but not sufficiently Funding source: National Institutes of Health; Nursing Research; National Heart, Lung, and Blood Institute
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not addressed in full by study authors: actual method of randomisation unclear
Allocation concealment (selection bias)	Unclear risk	Not addressed by study authors
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Evidence shows that steps were taken to ensure blinding
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Study authors reported: "Data were collected 4 times over the 12‐month study during home visits, scheduled at times convenient to the families, by RAs who were blind to group assignment"
Incomplete outcome data (attrition bias) All outcomes	Low risk	Study authors reported: "A total of 292 children were enrolled and 257 completed the 12‐month study (87.7% retention). There were no significant baseline differences in age, gender, race/ethnicity, SES, language spoken by parents, or asthma severity between the children who completed the study and those who dropped out"
Selective reporting (reporting bias)	Low risk	All collected outcomes apparently reported in full
Other bias	Unclear risk	Missingness ‐ unclear risk ‐ no evidence of additional missing data Baseline imbalance ‐ unclear risk ‐ children in the control group were more likely to be male; the impact that this could have on study outcomes is unclear Risk of contamination ‐ low ‐ schools were the unit of randomisation, lowering the risk of contamination
Transparent and clearly stated aims	Low risk	Study aims were clearly stated
Explicit theories underpinning and/or literature review	Low risk	Intervention was guided by Bruhn's theoretical model of asthma self‐management
Transparent and clearly stated methods and tools	Low risk	Study methods were clearly stated
Selective reporting	Unclear risk	A limited set of data was presented for the process evaluation
Harmful effects	High risk	Only a few negative outcomes were considered
Population and sample described well	Low risk	Study sample was well described
Continuous evaluation	Low risk	Data were collected at several time points
Evaluation participation equity and sampling	Unclear risk	Not many stakeholders were involved in the evaluation
Design and methods overall approach	Unclear risk	This is unclear, as risk of bias for outcome evaluation was low; however risk of bias for process evaluation was high
Tools and methods of data collection reliable/credible	Low risk	Tools used for data collection were credible
Tools and methods of data analysis reliable/credible	Low risk	Data analysis methods were appropriate for the data
Performance bias/neutrality/credibility/conformability	Unclear risk	Credible findings focused mainly on outcomes
Reliability of findings and recommendations	Low risk	Findings are transparent
Transferability of findings	High risk	Some factors around transferability were assessed, for example, reach and attrition; however no other factors were assessed
Overall risk of bias of process evaluation	Unclear risk	As an outcome evaluation, few concerns are evident; as a process evaluation, this study is questionable