Table 1.

Summary of instruments used at various times in the M528 trial.

Instruments	Baseline	Postpartum month
		1	2	3	4	5	6
Individual socioeconomic factors (participant and husband): age, sex, ethnicity, religion, education, occupation	x
Household factors: income level, wealth index	x
Previous pregnancy, childbirth and breastfeeding experience	x
Breastfeeding knowledge level (high/medium/low)	x
Intention and confidence to exclusively breastfeed	x
Breastfeeding self-efficacy scores (high/low)	x	x		x		x
Postdelivery survey: date of birth; place of birth; type of delivery; and child’s birth, weight, and sex		x
Child morbidity characteristics: signs and symptoms of fever, cough, respiratory tract infection, diarrhea, dysentery		x		x		x
Breastfeeding and other feeding follow-up module—24-hour recall and 1-month recall		x	x	x	x	x	x
Social desirability scale (high/medium/low)						x
Process evaluation on mHealth (intervention group only): frequency of text messages received, user-friendliness of the messages received, perceived relevance of messages, trust in messages, understanding of messages, and new information learned or not							x