Table 1 Summary study characteristics^a

Bourgeois 2008 [16]

US

RCT

Flu

Workplace

144 Healthy adults

Personally controlled health record program

Messages on influenza illness and prevention, tailored based on survey information provided and on postcode

Four monthly bulletins providing information on cardiovascular disease, stroke, skin cancer and sun protection, and guidelines for a healthy diet

16 weeks

● The rate of work attendance despite a respiratory illness,

● Question in exit survey on hand hygiene

● Question in exit survey on cough etiquette

Hu 2018 [17]

China

Non-randomised but controlled trial

HFMD

Kindergartens and home

10 staff, 60 parents and 60 healthy children

WeChat

WeChat education group (for GPs, staff, and parents) + Usual care

Usual care:

health education, delivered face to face.

3 months

● Incidence of HFMD

● Proportion of children who mastered the correct way of washing hands (measured at end of treatment)

● Proportion of children who formed good habits of washing hands (measured at end of treatment)

Hu 2019 [18]

China

RCT

HFMD

Community Health Service Center and home

Parents of 120 children with HFMD

WeChat

WeChat education group (for GPs and parents)

Usual care:

health education, delivered face to face.

14 days

● Duration of rash

● Time to recovery

Judah 2009 [19]

England

RCT

n/a

Service station bathrooms

Highway service station bathroom users, more than 198,000 restroom uses over 32 days

Text-only message, displayed on an electronic dot matrix

screen over the entryway to the 2 restrooms

14 different intervention messages covering seven domains, max 48 characters, all included the word ‘soap’.

Blank control:

no message on the board

Positive control:

“Wash your hands with soap.”

July–September 2008

● Soap use ratio

● Soap dispenser use divided by number of people in the bathroom during the intervention period (1-h intervals)

Little 2015 [9]

UK

RCT

RTIs

Online

20,066 adult patients from 344 practices, who had at least one other individual living in the household

Web-based and email prompts

Four weekly web-based sessions, that provided information, developed a plan for handwashing, reinforced helpful attitudes and norms, addressed negative beliefs and used tailored feedback.

Automated emails were used to prompt participants to use sessions and complete questionnaires

No treatment:

The control group did not have access to the intervention webpages, but they had monthly emails to prompt them to complete the questionnaires.

4 months

● Self-reported infections in user (incidence and severity of respiratory infections, incidence of gastrointestinal infections)

● Self-reported incidence of respiratory infections in household members

● Self-reported handwashing

● Health care use as assessed from medical records (number of GP consultations and antibiotic prescriptions)

Tidwell 2019 [20]

Study 2

India

RCT

n/a

Home

617 new mothers, 605 mothers of 4–7 year olds

Mobile phone audio messages (all); reminder texts (new mothers only)

Audio phone messages of 90s, twice weekly, conveying health messages via a fictional dialogue between a doctor and a mother; Text reminders to practice the target behaviours

No intervention (though control sample also had to own a phone)

8 weeks (new mothers),

4 weeks (mothers of 4–7 year-olds)

● Handwashing with soap at key occasions;

● Measured 21 days after the end of the intervention using sticker diaries

Wu 2020 [21]

China

RCT

HFMD

Home

3000 parents of vaccinated healthy children aged 0–3

Text messages

Messages of < 50 words, about knowledge, prevention and treatment of HFMD, sent at least weekly, with a total of 16–20 messages.

No intervention

5 months

● Proportion of children who wash hands before eating and after going to the toilet (measured at baseline and 1 year)

● Proportion of children who wash hands after going out (measured at baseline and 1 year)