Vargas‐Porras 2021.

Study characteristics
Methods	Study design: RCT Duration of study: the study was conducted from January to September 2019. Country: Colombia Income classification: upper‐middle income country in 2019 Geographical scope: Bucaramanga, Floridablanca, Girón, or Piedecuesta Healthcare setting: maternal‐child health care centre that is a national and regional referral centre for maternal‐child care and application of national healthcare standards; intervention delivered through home‐based and telephone‐based sessions.
Participants	1. Age: over 24 years in 66.67% (intervention group) and 48.48% control group; 24 years or under in 33.33% (intervention group) and 51.52% (control group) 2. Gender: female 3. Socioeconomic background: low in 48.48% (intervention group) and 72.73% (control); medium in 51.52% (intervention) and 27.27 (control) 4. Educational background: more than secondary school in 96.97% (intervention) and 69.70% (control) Inclusion criteria: a. living in Bucaramanga, Floridablanca, Girón, or Piedecuesta (Colombians who are culturally similar regarding beliefs about the care of mothers and infants, religion, mestizo ethnic group, and Spanish language); b. age ≥ 18 years; c. postpartum; d. first‐time mothers of healthy term infants; e. self‐reported partner support; f. owning a smartphone with internet access. Exclusion criteria: a. illiteracy; b. multiple pregnancies; c. postpartum depression; d. mental disorders; e. behavioural disorders; f. mother being admitted to the hospital or having her newborn admitted to an intensive care unit during the postpartum. Note: at baseline, the intervention and control group scores for Functional Social Support Subscale were, respectively, 76.12 (8.67) and 74.00 (10.58). Stated purpose: to test the efficacy of a multimodal nursing intervention (AMACOMPRI), based on Mercer's Becoming a Mother Theory, in supporting the process of becoming a mother in first‐time mothers of term infants
Interventions	Name: multimodal nursing intervention “Maternal Support for Becoming a First‐time Mother” (AMACOMPRI), in addition to usual postnatal healthcare Title/name of PW and number: 1 maternal and perinatal nursing expert with a master's degree and 15 years professional experience in postpartum education (first author) 1. Selection: not specified 2. Educational background: master's degree in nursing 3. Training: training occurred over 1 month by thoroughly rehearsing the protocol for each session following the intervention manual. 4. Supervision: two supervisors provided feedback to audio records to ensure consistent and compliant delivery. 5. Incentives/remuneration: not specified Prevention type: selective—participants were included based upon the presence of a risk factor (first‐time mothers) and presented with some level of distress as indicated by BaM and EPDS scores that were below the cut‐off for the measures. Intervention details: eight nurse‐delivered home‐based and telephone‐based sessions. The intervention was delivered by alternating four 90‐minute in‐person visits and four 15‐minute telephone calls. The first two sessions focused on functional social support, the second two on the mother‐infant bond, the third two on perceived maternal self‐efficacy, and the last two on becoming a mother. Control: usual care (usual postnatal care including (a) predischarge nursing guidance on postpartum care, newborn care, and breastfeeding; (b) an obstetric follow‐up appointment (at day 8 postpartum for vaginal delivery and day 10 after caesarean section) focused on detection and control of potential puerperal complications (e.g. wound inspection, monitoring for postpartum hypertension, or infection); (c) newborn follow‐up appointment (3 to 5 days postpartum) for assessment of adaptation to extrauterine life, nutritional state, and neonatal abnormalities or infection as well as providing breastfeeding advice)
Outcomes	Participants’outcomes of interest for this review Social outcomes (functional social support) – Functional Social Support Subscale from the Perinatal Infant Care Social Support Scale Note: maternal stress (BaM‐13 scale) and depression (EPDS) outcomes were only available for baseline. Carers’ outcomes of interest for this review Nil Economic outcomes Nil Time points: baseline, post‐intervention (< 1 month)
Notes	Source of funding: not specified Notes on validation of instruments (screening and outcomes): this instrument was translated into Spanish, culturally adapted, and validated in Colombian first‐time mothers of term infants (Vargas‐Porras 2020). Cronbach's α in the present study was 0.92. Additional information: none Handling the data: not applicable Prospective trial registration number: ClinicalTrials.gov (registration number NCT03594526)