Soto Mas 2018.

Study characteristics
Methods	Study design: RCT, 2 arms Geographic location: Texas, USA Ethical approval: yes Recruitment setting: general population Method of recruitment: local Spanish radio and television stations announced study Length of follow‐up: no follow‐up Dropouts: 18 in the intervention group and 8 in the control group were excluded from analysis (completed less than 75.0% of sessions) A priori calculation of effect size/power?: not reported
Participants	Description: Spanish‐speaking adults with low to intermediate English proficiency Health topic: Cardiovascular health, no specific health problems of participants reported Inclusion criteria Ability to read and write Spanish, ≥ 21 years of age, no previous participation in formal health/cardiovascular education/prevention programme, low to intermediate level of English proficiency, ability to read, write and speak English at a basic level Exclusion criteria Not reported Intervention group Health Literacy and ESL Curriculum (95 randomised and 77 analysed) Control group Conventional ESL Curriculum (86 randomised and 78 analysed) Note: only participants who completed more than 75% of the sessions were included in the final analysis. PROGRESS‐Plus Place of residence: urban, USA Time living in host country (years) (n = 145): 2.2% < 1 y, 12.7% 1 to 3 y, 8.3% 4 to 7 y, 70.2% 8 y or more, 6.6% missing Race/ethnicity: Latinos Gender: Intervention: 76.6% female Control: 84.6% female Education (n = 154): 5.2% elementary school, 11.7% middle school, 40.9% high school, 18.8% associate/technical degree, 20.1% bachelor's degree, 1.9% master's degree, 1.3% doctoral degree Age (years): 9.0% 20 to 30 y, 38.7% 31 45 y, 52.3% ≥ 46 y Note: complete data provided only for n = 155 analysed participants. Health literacy (baseline) Assessment tool, range, level: English TOFHLA (full version) 0 to 100, ≤ 59 inadequate, 60 to 74 marginal, 75 ≤ adequate Intervention group, mean (95% CI): 65.5 (62.1 to 68.9) Control group, mean (95% CI): 59.9 (56.1 to 63.8)
Interventions	Intervention: Health literacy and ESL curriculum Theoretical framework: theories of health literacy and health behaviour, sociocultural approaches to literacy and communication, Adult Learning Theory Description: the intervention consisted of a conventional ESL course, which was extended by health literacy‐related content and skills development. It focused on improving English proficiency in listening, speaking, reading and writing while developing health literacy and cardiovascular disease prevention knowledge skills. The health literacy curriculum consisted of 12 separate units that opened with a vignette in Spanish language describing the experiences with health and the healthcare system of a recently arrived immigrant family. The content addressed the development of skills related to prose, documents, numeracy, clinical practices, preventive practices and navigation of the health care system. Intervention provider: trained ESL teacher Delivery method/mode: 12 face‐to‐face, group sessions lasting 3.5 hours (total of 42 hours) delivered over a period of 6 weeks Language of delivery: English/Spanish Format: standard Setting/location: 3 community colleges Consumer involvement: evaluated with participants of the intervention Comparator Type: usual care (standard ESL course without additional information) Description: a second teacher delivered conventional curriculum to all control groups, the conventional ESL programme is not specific to health literacy but, it includes content related to civic and life skills (e.g. make an appointment, use community resources, communicate schedule information) and maths (e.g. complete a bar graph, calculate net pay), in addition, 2 units are related to health “ailments and injuries,” and “food and nutrition.” Note: standard ESL curriculum already includes health related topics. Therefore, control group assignment might not be accurate.
Outcomes	Outcomes assessed in the study: functional health literacy, cardiovascular health behaviour Outcomes considered in this review Health literacy Functional health literacy Health behaviour (cardiovascular health behaviour) Methods of assessing outcomes Self‐administered questionnaires, health literacy assessment, but in group setting; general completion instructions were read out loud to the group. Functional health literacy: English version of TOFHLA, 0 to 100, ≤ 59 inadequate, 60 to 74 marginal, 75 ≤ adequate, higher score is better Cardiovascular health behaviour: Cardiovascular Health Questionnaire (CSC), 34 to 136, higher score is better Language of assessment: English (health literacy) and Spanish (health behaviour) Translation procedure: the CRC was a translated version; not reported for health literacy Reliability/validity: validated tools Timing of outcome assessment: baseline and short‐term (immediately after intervention at 6 weeks after first session)
Health literacy	Definition: “The degree to which individuals can obtain, process, and understand the basic health information and services they need to make appropriate health decisions.” (Ratzan 2000, pp. v‐vi) Health literacy components addressed by the intervention Prerequisites and tools Knowledge Motivation Competences Steps of information processing Access Understand Appraise Apply Health domain: disease prevention
Notes	Trial ID: not reported Funding: funding was provided by the National Heart, Lung, and Blood Institute, National Institutes of Health (Title: Health Literacy and ESL: Integrating Community‐Based Models for the U.S.‐Mexico Border Region. No. 1R21 HL091820‐01A2. PI: Francisco Soto Mas). Additional notes: the study was reported in multiple publications. For an overview of the included reports linked to this study, see (Soto Mas 2018). Gendered scores for health behaviour were provided by the study authors.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"Those who met all requirements were randomly assigned to either the intervention or control group. When more than one family member or relative qualified, only one person per household was selected for the study." "Years in the US (P=0.024) and level of education (P=0.022) were the only demographic variable unbalanced between intervention and control at baseline with controls more likely to have lived in the US longer and more likely to have less than high school education. The intervention group had higher TOFHLA and higher numeracy scores at baseline compared to controls." Insufficient information to permit judgement of low risk or high risk, as the method of randomisation is not reported.
Allocation concealment (selection bias)	Unclear risk	No statement on allocation concealment. Therefore, information is insufficient to permit judgement of low risk or high risk.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Due to the nature of the study, blinding of participants and personnel was not possible and cardiovascular health behaviour was subjectively measured.
Blinding of outcome assessment (detection bias) subjective outcome measures	High risk	Cardiovascular health behaviour was measured via self‐report and participants were not blinded to group allocation. This might have introduced bias.
Blinding of outcome assessment (detection bias) objective outcome measures	Low risk	Participants and personnel were not blinded but health literacy was objectively measured and not subject to interpretation.
Incomplete outcome data (attrition bias) All outcomes	Low risk	"All participants who attended the last session completed the posttest. Only participants who completed more than 75% of the sessions were included in the final analysis." The dropout rate was higher for the intervention group compared to the control group (N = 18 vs N = 10); no intention‐to‐treat analysis was performed, but a completers only analysis was done. However, reasons for dropouts were transparently given, and intervention and control only differed in their content, so that the imbalanced dropout rate was presumably not caused by the intervention.
Selective reporting (reporting bias)	Low risk	All outcomes reported in the methods were reported in the results of the publications.