Of the 55 studies included in this review, there were 10 RCTs, four cohort studies, seven quasi-experimental (open, nonrandomized trial), 27 cross-sectional, five mixed-methods (pre-and post-intervention with qualitative component), and two qualitative studies. We used the World Bank income level classification to categorize the countries where the study was conducted [27]. Thirty-four studies were conducted in high-income countries (HIC): United Kingdom (n = 3), United States (n = 5), Australia (n = 3), Norway (n = 1), and Japan (n = 22). Twenty-one studies were conducted in low- and middle-income countries (LMIC): Indonesia (n = 3), Kenya (n = 3), Mongolia (n = 2), Pakistan (n = 2), and one study in Vietnam, South Africa, Brazil, Bangladesh, Palestine, Burundi, Uganda, Dominican Republic, Cambodia, Bosnia and Herzegovina, and one multi-country study. Table S4 shows the study settings, population descriptions, and interventions conducted.

We noted differences in the inclusion criteria of the study populations. Mothers’ enrollment period varied across the studies, from any time during pregnancy, childbirth, and the postpartum period. One study was conducted in 13 centers in eight countries and targeted both literate and illiterate mothers living in different geographical and cultural conditions and communities with low or easy access to health services [28]. In this review, most studies were conducted in health facilities, and a few were conducted in community settings.

We also noted differences in the type of interventions. Of 55 studies, 34 focused on the MCH handbook, and the remaining 21 focused on other home-based records, such as maternity case notes, road to health (RTH) booklet, personal child health record, among others. Some studies did not have a comparison group, while others were compared to standard care or non-users of home-based records. Hence, the results were reported considering home-based records as a single intervention. Overall, the studies were heterogeneous, and the sample sizes mainly varied (range: 5–5,940,204) (Table S4).

We noted differences in the risk of bias across the studies. Figure 2 shows the risk of bias assessment for the 10 RCTs included in this review [29]. Following the RoB 2 algorithm, all selected studies had a high overall risk of bias, mainly owing to bias from the randomization process, blinding/masking not described or not possible for the said intervention, and selective outcome reporting. For non-RCTs, the results of the risk of bias assessment are shown in Table S5. We found some methodological considerations and critical potential confounding variables neither measured nor adjusted statistically.

Eight studies assessed the roles of home-based records on newborn health [6,7,28,30,31,32,33,34] (Table 1). Findings suggested a positive effect of home-based records on newborn care seeking (n = 2) and newborn care knowledge (n = 2). In Burundi, the proportion of mothers who sought postnatal care (PNC) from health personnel after delivery significantly increased from 35.9% to 64.2% after using the MCH handbook (p < 0.05, 95% CI: 59.2–69.3%) [30]. In South Africa, the proportion of HIV PCR birth tests registered with the RTH booklet identifier reached > 50% after only six months, suggesting that the RTH booklet can successfully be leveraged to provide infants with a unique patient identifier at birth [31]. In Indonesia, the mother class used the MCH handbook as the main reference material during the educational sessions [32]. Attending mothers showed improvement in knowledge regarding immediate breastfeeding (OR = 2.79, 95% CI: 1.48–5.25), giving colostrum (OR = 2.09, 95% CI: 1.09–4.02), exclusive breastfeeding duration (OR = 3.54, 95% CI: 2.04–6.15), use of antibiotic for newborn’s eyes (OR = 4.58, 95% CI: 3.05–6.88), hepatitis B immunization at birth (OR = 1.56; 95% CI: 1.06–2.28), thermal protection (OR = 3.99, 95% CI: 1.59–10.06), cord care (OR = 8.86, 95% CI: 5.69–13.8), and recognition of danger signs in newborns (OR = 3.29, 95% CI: 2.15–5.05) [32]. Indonesian mothers who used the MCH handbook were more likely to practice good newborn care than the standard care group (OR = 1.81, 95% CI: 1.24–2.66) [32]. Similarly, a multi-country study showed that mothers who used home-based maternal records became more involved in looking after their health and newborns [28].

However, findings suggest no significant effects of home-based records on immediate breastfeeding (n = 2), neonatal deaths (n = 2), or APGAR (i.e., appearance, pulse, grimace, activity, and respiration) score (n = 1). One RCT conducted in the UK showed no significant difference between mothers in the case note group and cooperation card group about breastfeeding after delivery (78.9% vs. 77.4%, respectively) and the incidence of neonatal deaths (both 2.0%, GRADE certainty of evidence: very low) [34]. The same results were obtained in one cluster RCT conducted in Mongolia [7]. A higher rate of immediate breastfeeding initiation was observed among mothers who received the MCH handbook (versus no handbook); however, there was no significant difference (RR = 1.07, 95% CI: 0.97–1.18, GRADE certainty of evidence: moderate) [7]. Moreover, there was no significant difference in either neonatal deaths (RR = 1.00, 95% CI: 0.99–1.02, GRADE certainty of evidence: very low) or APGAR scores (MD = 0.21, 95% CI: −0.21–0.63, GRADE certainty of evidence: moderate) using the MCH handbook compared with the control group [7].

We found evidence on the positive effects of home-based records on childcare seeking (n = 6) and vaccination uptake and recording (n = 10) (Table 2).

Mothers who received home-based records were more likely to utilize healthcare services [6,51,52,53,54,55] and adhere to the recommended immunizations and childcare visit recommendations [42,43,44,45,46,47,48,49,50,56,57]. However, a mixed effect was obtained concerning age-appropriate immunization, such as a three-dose series of diphtheria, tetanus toxoids, and pertussis (DTP) [35,36,37,38]. Findings in randomized trials conducted in the UK and USA suggested no significant effects on the DTP3 completion rate among children using home-based records compared to no home-based records (pooled RR = 0.89, 95% CI: 0.64–1.24, GRADE certainty of evidence: very low) [35,36]. In contrast, in an RCT conducted in Pakistan, children who were using a redesigned immunization card showed significant improvement in the DTP3 completion rate compared to a standard expanded program on immunization (EPI) card (pooled RR = 1.46, 95% CI: 1.09–1.94, GRADE certainty of evidence: moderate) [37,38].

Six out of 16 studies showed a positive effect of home-based records on child healthcare knowledge. Mothers who used home-based records showed improvement in their knowledge of general health [51], immunization [56], exclusive breastfeeding [56,62,63], biliary atresia [65], and infant accident prevention [68]. Among less-educated Japanese women who are literate, the MCH handbook effectively provided adequate knowledge about exclusive breastfeeding [62]. Similarly, mothers who had read the MCH handbook were more careful of infant accidents than a group of mothers who had never read the handbook (p < 0.01) [68]. On the other hand, a few studies reported no effect/mixed results related to immunization [59,60,61], detection of biliary atresia [64,66], and sudden infant death syndrome [67]. Japanese mothers requested more information on the vaccination schedule, stool color card, and sudden infant death syndrome.

Most studies reported an improvement in child health practices (n = 8) and illness management (n = 3) among recipients of home-based records. A significant change in exclusive breastfeeding practice was seen among mothers who received the MCH handbook in Bangladesh (16.9% vs. 0.7%) and Vietnam (74.9% vs. 18.3%) [56,63]. However, one RCT conducted in Indonesia showed no effect of the MCH handbook on exclusive breastfeeding for six months (OR = 0.76, 95% CI: 0.51–1.14, GRADE certainty of evidence: low) [6]. Despite this opposite result, the authors reported that Indonesian mothers who received the MCH handbook tended to practice continued breastfeeding (OR = 2.31, 95% CI: 1.22–4.39), complementary feeding (OR = 4.35, 95% CI: 2.85–6.65), proper feeding order (OR = 2.70, 95% CI: 1.79–4.09), varied foods feeding, e.g., by providing fruits and/or fruits extract (OR = 2.18, 95% CI: 1.42–3.36), and self-feeding training (OR = 2.75, 95% CI: 1.74–4.36) [6] (GRADE certainty of evidence: moderate). In a similar study, mothers who received the MCH handbook tended to practice home care for cough (OR = 3.50, 95% CI: 1.44–8.52, GRADE certainty of evidence: low) and vitamin A use (OR = 2.00, 95% CI: 1.16–3.47, GRADE certainty of evidence: moderate) [6]. The study did not show a significant difference between the intervention and control arm for home care for diarrhea (83.3% of 24 cases, 92.6% of 27 cases) [6]. In contrast, growth monitoring seemed to concern mothers who received a home-based record. Mothers ignored developmental indicators that they did not understand, such as head circumference [72] and growth curves (e.g., weight-versus-age chart, BMI-versus-age chart) [73,75]. Further explanation may have supported mothers to address this issue. In Japan, reading and completing the MCH handbook were associated with maternal characteristics, with older mothers and mothers with little childcare experience completing the handbook more [74].

Two randomized studies showed evidence related to child mortality and morbidity [6,78]. In Indonesia, mothers who received the MCH handbook were less likely to have underweight children (OR = 0.33, 95% CI: 0.12–0.94, GRADE certainty of evidence: very low) and children with stunted growth (OR = 0.53, 95% CI: 0.30–0.92, GRADE certainty of evidence: low) [6]. However, no significant difference was observed between the intervention and control arm concerning wasting among children [6]. In Mongolia, MCH handbook users showed a reduction in the risk of children’s cognitive delay compared with the control group at a three-year follow-up (AOR = 0.32, 95% CI: 0.14–0.73, GRADE certainty of evidence: very low) [78].

Seven out of eight studies showed a positive effect of home-based records on the continuum of care [6,28,30,49,63,79,80]. Among all home-based records, the MCH handbook showed evidence of the continuum of maternal, newborn, and childcare. In Vietnam, the proportion of pregnant women who made ≥ 3 antenatal care (ANC) visits and practiced exclusive breastfeeding significantly increased between pre- and post-intervention (p < 0.001) [63]. In Burundi, the proportion of mothers who received birth notification at health facilities significantly increased from 4.6% to 61.0% (p < 0.05, 95% CI: 55.9–66.2%) [30]. In the Dominican Republic, the rate of mothers receiving antenatal and postpartum care at designated clinics or hospitals increased from 13% to 40% [49]. In Japan, mothers who had seen their own MCH handbook when they were young had a higher continuity awareness than those who had not [80]. The MCH handbook also strengthened the collaborative interactions among hospitals, local government units, and schools [81]. However, more effort is needed to translate the positive utilization of the MCH handbook into personal responsibility for health [81].