Opaque Bottle Study

A Pilot-Feasibility of a Home-based Intervention to Reduce Obesity Risk for Bottle-fed Infants

The proposed research aimed to conduct an intervention study assessing the effect of feeding mode (clear versus opaque bottle) on the quality and outcome of infant feeding interactions.

Study Overview

• Status: Completed
• Conditions: Opaque Bottles; Conventional, Clear Bottles
• Intervention / Treatment: Other: Opaque Bottle; Other: Clear Bottle

Detailed Description

The overall objective of the proposed pilot/feasibility study was to evaluate a home- and family-based intervention to increase bottle-feeding mothers' responsiveness to infant satiety cues and moderate bottle-feeding infants' rates of weight gain over a 12-week period. Specifically, the investigators propose to provide mothers with opaque, weighted bottles (instead of conventional, clear bottles) with which to feed their infants; based on preliminary studies, it is hypothesized that removal of mothers' abilities to assess the amount the infant consumes during feeding will facilitate abilities to feed in response to infant satiation cues.

For the proposed research, predominantly bottle-feeding mothers with <6-month-old infants were randomized to use opaque bottles (intervention or opaque group) or to use clear bottles (control or clear group). The investigators conducted home-based assessments at the beginning and end of the 12-week study period during which mothers were video-recorded feeding their infants using clear or opaque bottles. Two interim assessments will be conducted (after 2 and 6 weeks) to assess feeding adequacy and fidelity to the intervention. During feeding observations, infant intake were assessed via bottle weight. Video-records were later coded for maternal responsiveness to infant cues using the Nursing Child Assessment Parent-Child Interaction Feeding Scale (NCAFS). It was hypothesized that mothers in the opaque group will feed their infants less and show greater increases in their levels of responsiveness to infant cues compared to mothers in the clear group. Infants' weight and length were measured at the beginning and end of the 12-week study; weight-for-length z-scores (WLZ) were calculated using the World Health Organization (WHO) Growth Standards. It was hypothesized that WLZ change would be significantly lower for infants in the opaque compared to the clear group. The feasibility of the intervention was also explored by collecting and analyzing objective and subjective data related to the extent to which mothers use and like the bottles, and whether characteristics of mothers or infants moderate intervention effects. The proposed feasibility study is a critical step toward understanding mothers' acceptance and use of opaque bottles compared to conventional, clear bottles, and the potential for opaque bottles to improve the outcome of feeding interactions in home-based settings.

• Study Type: Interventional
• Enrollment (Actual): 152
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Alison K Ventura, PhD; Phone Number: (805)756-5693; Email: akventur@calpoly.edu
• Study Contact Backup: Name: Noemi Alarcon; Phone Number: (805)756-5694; Email: noalarco@calpoly.edu

Study Locations

• United States
  • California
    • San Luis Obispo, California, United States, 93401
      • Healthy Kids Laboratory within the French Hospital Copeland Health Education Pavilion

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 1 second to 40 years (Child, Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• mothers 18-40-years of age
• infants <24-weeks of age
• predominantly bottle-feeding (>50% of feedings)
• mother predominantly or solely responsible for infant feeding
• dyad has a pediatrician and plans to attend infant well-visits
• mother is willing to use stainless-steel bottles and to provide the study with her current bottles, which would be returned after study completion
• prior to the introduction of solid foods.

Exclusion Criteria:

• preterm birth (i.e., gestational age <37 weeks)
• low birth weight (<2500 g)
• maternal smoking during pregnancy
• current or past medical conditions that interfere with oral feeding
• history of slow growth or failure to thrive
• weight for length percentile <5th
• diagnosed developmental delay (e.g., Down's syndrome)
• currently using opaque bottles

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Opaque Bottle Group; This group was given a set of opaque bottles to use during infant feedings for a full 12-week period.	Other: Opaque Bottle; These mothers received everything provided to the clear group, but instead received 12 opaque bottles of various sizes (4-12 ounces). These bottles were stainless steel and compatible with a variety of different nipples manufactured by a leading bottle company. Mothers in the intervention group also received an additional handout that contained safety tips for their opaque bottles (e.g., never microwave your bottle).
Active Comparator: Clear Bottle Group; This group was given a set of clear bottles to use during infant feedings for a full 12-week period.	Other: Clear Bottle; These mothers received usual care from their pediatric providers and each mother was given 12 conventional, clear bottles of various sizes (4-12 ounces) that were compatible with a variety of different nipples manufactured by leading bottle companies. Mothers were also given handouts about proper formula preparation and paced bottle-feeding, which included messages about feeding in response to infant cues.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Infant Intake (mL) During the Observed Feeding	During post-tests, participants in both the Clear Bottle and Opaque Bottle Groups were asked to use the clear bottle during one feeding observation and the opaque bottle during the other feeding across the two post-test assessments, which ensured research assistants remained masked to whether the participant was in the intervention or control group and allowed for within-subject comparison of effects of clear versus opaque bottles on maternal sensitivity and infant intake; order of bottle presentation was counterbalanced. For both opaque and clear bottle-feedings, infant intake was assessed by weighing the infant's bottle before and after each feeding observation using a top-loading balance (SP601 Scout Pro Portable Balance, Ohaus, New Jersey, USA).	12-week period
Maternal Sensitivity to Infant Cues	Mothers' behavior during feeding observations was coded using the Nursing Child Assessment Parent-Child Interaction - Feeding Scale (NCAFS). This scale contains six subscales, four of which describe maternal attributes (Sensitivity to Cues, Response to Child's Distress, Social-Emotional Growth Fostering, and Cognitive Growth Fostering) and two of which describe infant attributes (Clarity of Cues and Responsiveness to Caregiver). The present analysis focused on the Sensitivity to Cues subscale, which measures the degree to which the mother is able to understand and respond to her child's cues. This scale provides a global measure of how sensitive the mother is to the infant's needs during the feeding interaction. Possible score range is 0-16, which is derived from summing together maternal scores for each of the 16 subscale items. Higher scores indicate greater sensitivity to infant cues.	12-week period
Infant Weight-for-length Z-scores	Infants' weight and length were assessed during home-based assessments. Infant weight and length were measured in triplicate using a portable infant scale/infantometer. To minimize bias, infants were always weighed and measured while only wearing a clean diaper and prior to the observed feeding. Weight and length values were standardized to age- and sex-specific weight-for-length z-scores based on the World Health Organization Child Growth Standards (https://www.who.int/tools/child-growth-standards). A z-score of 0 indicates that the child's weight status is at the population median; standard deviations closer to 0 represent healthier weight status. Standard deviations below 0 indicate the child's weight status is below the median, with values < -2 indicating the child is underweight. Standard deviations above 0 indicate the child's weight status is above the median, with values > 2 indicating the child is overweight or obese.	12-week period

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Infant Waist Circumference	Infant central adiposity was assessed via a waist circumference measurement, which was assessed during home-based assessments by trained research assistants. Waist circumference was assessed in triplicate using a study-specific Gulick II tape measure.	12-week period
Change in Infant Triceps Skinfolds z-Scores	Triceps skinfold thickness, a marker of infant adiposity, was assessed during home-based assessments by trained research assistants. A study-specific Harpenden caliper was used for this assessment. Triceps skinfold thickness values were standardized to age- and sex-specific z-scores based on the World Health Organization Child Growth Standards (https://www.who.int/tools/child-growth-standards). A z-score of 0 indicates that the child's adiposity is at the population median. Standard deviations below 0 indicate the child's adiposity is below the median and standard deviations above 0 indicate the child's adiposity is above the median. Standard deviations closer to 0 represent healthier levels of adiposity.	12-week period
Change in Infant Subscapular Skinfolds z-Scores	Subscapular skinfold thickness, a marker of infant adiposity, was assessed during home-based assessments by trained research assistants. A study-specific Harpenden caliper was used for this assessment. Subscapular skinfold thickness values were standardized to age- and sex-specific z-scores based on the World Health Organization Child Growth Standards (https://www.who.int/tools/child-growth-standards). A z-score of 0 indicates that the child's adiposity is at the population median. Standard deviations below 0 indicate the child's adiposity is below the median and standard deviations above 0 indicate the child's adiposity is above the median. Standard deviations closer to 0 represent healthier levels of adiposity.	12-week period
Mothers' Perceptions of the Bottles	Mothers' perceptions of their assigned bottles, including any perceived barriers to their use, were assessed via a questionnaire developed by the investigators.	12-week period

Collaborators and Investigators

• Sponsor: California Polytechnic State University-San Luis Obispo
• Collaborators: Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
• Investigators: Principal Investigator: Alison K Ventura, PhD, California Polytechnic State University-San Luis Obispo

Publications and helpful links

General Publications

• Ventura AK, Pollack Golen R. A pilot study comparing opaque, weighted bottles with conventional, clear bottles for infant feeding. Appetite. 2015 Feb;85:178-84. doi: 10.1016/j.appet.2014.11.028. Epub 2014 Nov 28.
• Ventura AK, Hernandez A. Effects of opaque, weighted bottles on maternal sensitivity and infant intake. Matern Child Nutr. 2019 Apr;15(2):e12737. doi: 10.1111/mcn.12737. Epub 2018 Nov 22.

Study record dates

Study Major Dates

• Study Start (Actual): December 1, 2018
• Primary Completion (Actual): July 10, 2022
• Study Completion (Actual): July 10, 2022

Study Registration Dates

• First Submitted: October 14, 2018
• First Submitted That Met QC Criteria: October 16, 2018
• First Posted (Actual): October 18, 2018

Study Record Updates

• Last Update Posted (Actual): August 23, 2023
• Last Update Submitted That Met QC Criteria: July 31, 2023
• Last Verified: July 1, 2023

More Information

Terms related to this study

• Keywords: infant feeding; maternal feeding practices; feeding interactions; bottle-feeding; opaque bottles
• Other Study ID Numbers: 2018-164-CP; R21HD096236 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: We do not currently plan to make individual participant data available to other researchers.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No