TABLE 1 Coding Scheme to Describe Messages Posted by WhatsApp Learning Group Participants, Kibera and Makueni, Kenya, August 19, 2014 – March 1, 2015– (N = 1,830 Posts, Codes Listed in Alphabetical Order)

Code	Description	No. of Posts^a	Code	Description	No. of Posts^a
Chain letter	Generic message forwarded to members	12	Mobile app	References to child developmental milestones or the project app	46
Clarifications	Corrections to a prior post	11	Mobile phone	Operational aspects of using mobile phones	113
Community development	Community mobilization efforts in Kibera or Makueni	35	Moral support	Condolences and encouragement in response to challenges or hardships	133
Disability	Documentation of disabled child’s developmental milestones	111	Mutual learning	Informal learning, peer learning, and knowledge exchange	108
Encouragement and praise	Encouragement and praise in response to a prior post	281	Other health initiatives	References to health programs other than childhood disability, malnutrition, or water and sanitation	110
Evidence	Documentation of CHW practice	14	Other media	Posts containing only icons, videos, or audio and exclusive of text	19
Follow-up	Responses to a prior post or event	120	Photos	Posts of photos	411
Fundraising and donations	Collection or distribution of money or objects	16	Photo captions	Posts containing descriptions of photos	183
Greetings	Hellos, welcome messages, and holiday wishes	215	Referral	Referrals of patients to CHEW or health facility	79
Health education	CHW efforts to educate community	31	Religion	Bible verses, blessings, and other references to faith	108
Household visits	Encounters during CHW household visits	51	Reporting	CHW descriptions of patient encounters or community work	100
Inspiration	Words to motivate forum participants	48	Reprimand	Posts that discipline or challenge other WhatsApp participants	16
Job offers and professional development	Employment announcements and outside training	22	Requesting information	Solicitation of additional information from others	83
Kibera-Makueni exchange	Communication between Kibera & Makueni participants	137	Security	References to community violence, fires, or other disturbances	4
Kenya	Nation building	8	Service	Statements about community service	6
Logistics and planning	Time, date, location, and agenda of meetings and other events	186	Thanks	Expressions of gratitude	304
Malnutrition	Descriptions of work with malnourished children	16	Training	Formal learning opportunities	122
mLearn project	References to the mLearn project and its site visits, conferences and training activities	297	Water and sanitation	Initiatives to promote clean water and hygiene	42

↵a More than 1 code may have been assigned to any 1 post, so percentages will not total to 100%.