Table 1 Definition and measures of research instruments

1.The maternal record form

Sociodemographic^a

maternal age, marital status, and household income

NA

access to healthy food^a

ability of pregnant women to access low-fat food (i.e., lean meat, white fish, egg white, dried beans, fresh/frozen vegetables, baked or boiled potatoes) options and distance from their home to the nutritional environment [8, 9, 14, 23]

2

4-point scale; once a month to more than once a week; less than 2 km to more than 6 km

- Access was the sum of two ability measures. Range 2 to 8, higher scores (6–8) categorized as, "easy access to low-fat food."

Obstetric data^b

parity, medical condition, pre-pregnancy BMI, and received GWG advice

Gestational Weight Gain^b

Total Gestational Weight Gain (TGWG) according to the IOM recommendations for the overweight/obese group [8, 10] that calculated from the mother's last weight in kilograms at the time of admission for delivery minuses pre-pregnancy weight

3 categories of GWG; inadequate to excessive

Total GWG (kilogram) of pregnant women

Type of GWG

Adequate

7–11.5

5–9

Inadequate

 < 7

 < 5

Excessive

 > 11.5

 > 9

-Pregnancy Induce Hypertension (PIH)^b

a systolic blood pressure reading ≥ 140 mmHg and/or a diastolic blood pressure ≥ 90 mmHg (average of at least 2 measurements taken at least 15 min apart) [2]

-LGA^b

neonatal birthweight > 90^th percentile for gestational age [1]

-SGA^b

neonatal birthweight < 10^th percentile for gestational age [1]

-macrosomia^b

neonatal birthweight > 4000 g [1]

2.The questionnaires on health cognitions and health behaviors

-Knowledge^a

the information or understanding of information about healthy eating, physical activity (PA), and weight gain [17]

11

True/False; one response recorded to correct/incorrect

Number of items with correct responses. Range 0–11, higher scores (9–11) categorized as "adequate GWG knowledge"

S-CVI 0.9

-KR21 0.63

-Weight locus of control^a

the belief that body weight is under self-control (internal WLOC) or caused by the environment surrounding respondents (external WLOC) [17]

4

5-point scale; strongly disagree to strongly agree

Mean of all items in measure with external items reverse scored. Range 1 to 5, higher scores (18–20) categorized as "internal WLOC"

Cronbach α

0.71

-Social support^a

Perceived support from husband or friends regarding healthy eating, physical activity, and gestational weight control [17]

13

5-point scale

A sum of scores from each individual construct. Range 13 to 65, higher scores (50–60) categorized as "high social support"

Cronbach α

0.63

-Perceived barriers^a

The respondents' perception on limitations, constraints, or barriers regarding healthy eating and PA [17]

12

5-point scale

A sum of two barrier measures. Range 12 to 60, higher scores (48–60), categorized as "high barriers."

Cronbach α

0.71

-Intention^a

An individual's explicit decisions to behave in a certain way concerning healthy eating, PA, and weight gain [17]

7

7-point scale

A sum of scores from each individual construct. Range 7 to 49, higher scores (39–49), categorized as "high intention."

Cronbach α

0.68

Healthy food consumption^a

The respondents' health practices that relate to dietary consumption patterns, food preparation, and type of food consumed [12]

28

4-scale; never to always

Range 28 to 112, higher scores (78–112), categorized as "appropriate healthy food consumption."

S-CVI 0.9

Cronbach α

0.85

Physical Activity^a

The respondents' health practices that relate to work/job-related activities, housework, hobbies and travel, exercise activity, and relaxation activity [12]

16

4- point scale

Range 16 to 64, higher scores (45–64), categorized as "appropriate PA."

Cronbach α

0.87

3.The ANC service provision questionnaire

-Quality of ANC service provision (general/specific)

The level of care provided to pregnant women [39, 40], derived from the calculation of the percentage score regarding ANC services provision in each ANC unit compared with the standard from literature review [26,27,28, 35,36,37]

The general service provision in ANC unit regarding screening for anemia, thalassemia, parasite, STD and other infectious diseases, preeclampsia screening at every ANC visit, GDM screening at 1^st visit and 24–28 weeks of gestational age, provision of supplements, group nutrition education, evaluation of nutrition and weight gain status, recording nutrition graph or weight gain chart, and making ANC appointments

24

2 - point scale; does exist and does not exist

The percentage score of ANC services provision in each ANC unit was calculated, Range 0–100, the quality level of ANC service provision was categorized [39, 40] as follows: very good (meet completely, 100%), good (meet mostly, 80–99%), fair (meet fairly, 50–79%), poor (must be improved, 2–49%)

S-CVI 1

Cronbach α

0.85

general

10

specific

The specific service provision in ANC unit regarding weight and height measurement at 1st ANC visit, weight measurement at every ANC visit, medical prevention for maternal and neonatal complications during pregnancy, individual nutrition education, preeclampsia screening in women with Class III obesity, GDM screening at 1^st ANC visit, ultrasound examination, food consumption assessment, referral to a multidisciplinary team for delivery planning, anesthesia consultation, and providing specific intervention for GW control

14

4. The healthcare provider's questionnaire

GWG knowledge^d

the accuracy and suitability of recommended GWG, food consumption, and physical activity information that healthcare providers provided to pregnant women [25]

11

5-point scale; strongly disagree to strongly agree

Ranged 11 to 55, high mean scores of knowledge (44–55), categorized as " indicated adequate GWG knowledge"

S-CVI 1 Cronbach α

0.81

Attitude toward GW control^d

The importance of GWG management in pregnant women with overweight/obesity in terms of discussion, assessment, and assistance [25]

3

5-point scale

Ranged 3 to 15, high mean scores of Attitude toward GW control (14–15), categorized as "positive attitude"

Cronbach α

0.78

GWG counseling practice^d

the process of professional relationships between healthcare providers and pregnant women with overweight/obesity for providing specific advice and information regarding GWG, nutrition, dietary consumption, and physical activity [25]

18

5-point scale; almost never to almost

Ranged 18 to 90, high mean scores of GWG counseling practice (63–90), categorized as "routine GWG counseling practice"

Cronbach α

0.79