Using new technologies to promote weight management: a randomised controlled trial study protocol

Participants

A cohort of 120 overweight and obese individuals with a body mass index (BMI) between
25–40 kg/m² and aged between 21 and 65 years will be recruited from the Perth community via flyers
posted at community noticeboards, advertisements in local newspapers and advertisements
on local community radio stations. Eligible participants will also be required to
have access to a computer, laptop, tablet or Smartphone. Exclusion criteria will include
smoking, lipid lowering medication, use of steroids and other agents that may influence
lipid metabolism, use of warfarin, diabetes mellitus, hypo- or hyperthyroidism, cardiovascular
events within the last 6 months, major systemic diseases, gastrointestinal problems,
proteinuria, liver disease, renal failure, weight fluctuations over the past 6 months,
vegetarianism or participation in any other clinical trials within the last 6 months.
All participants will be required to provide written informed consent before the trial
commences. All identifiable information from participants will be coded. This study
will be conducted according to the ethical guidelines that are specified in the Curtin
University Human Research Ethics Committee (HREC) and the National Health and Medical
Research Council (NHMRC) guidelines. This trial has been approved by the Curtin University
HREC (approval number: HR90/2014) and has been registered with ANZCTR (registration
number: ACTRN12614000536662), on 21 May 2014.

Study design

This will be a three-armed, randomised, controlled, parallel design intervention study
undertaken over a 12 week period, with a subsequent 12 week follow-up. Interested
participants will be screened according to the inclusion/exclusion criteria and those
eligible will be allocated a number, stratified according to age and gender, and then
randomly allocated to one of the three groups of 40 participants, using dedicated
computer randomisation software 41], 42] The allocated number will also be used as the participants’ identification number,
to be used on all records and questionnaires. The three groups will consist of: the
Control Group who will follow the Australian dietary guidelines 39] and National Physical Activity Guidelines for Adults 16], the Pamphlet Group who will be instructed in the weight management program by written
information, and the social media group who will receive exactly the same weight management
program via Facebook in the Facebook Group. [Please see Fig. 1: Flow of participants.] The initial twelve-week weight management program will be
presented to the two intervention groups as a condensed version of the CSIRO TWD 17], which includes information of the weight management program, along with weekly checklists
available from the CSIRO TWD 43]. Before the commencement of the trial, participants will attend an information session
specific to their group allocation, where the participation requirements, including
questionnaires and outcome measurements, will be explained. An additional file explains
this in greater detail [please see Additional file 1]. During the Facebook Group information session, participants will be provided with
additional information about using Facebook in this context. Facebook Group participants
will also be made aware of the role of the primary investigator as administrator and
facilitator of the Facebook Group. In addition, participants in this group will be
informed that at the completion of the twelve-week intervention period, all facilitation
will cease, however the group will still be monitored by the facilitator to ensure
that they continue to conduct themselves according the instructions provided. This
change in strategy for the twelve-week follow-up period will be used to determine
whether the Facebook Group has become self-sustaining. An additional file explains
the added information provided for Facebook Group participants in greater detail [please
see Additional file 2].

Fig. 1. Flow of participants

Outcome measures

The primary outcome measures for this study is weight loss, body composition and waist
circumference. Secondary outcome measures include blood glucose, insulin and lipids,
blood pressure, arterial stiffness and hip circumference, as indicators of changes
to cardiometabolic disease risk factors. Dietary and physical activity compliance,
eating behaviour, quality of life, mental well-being (stress, anxiety, and depression),
self-control, self-efficacy, Facebook activity, and program evaluation will also be
evaluated as further secondary outcome measures. These clinical and self-reported
measurements have been chosen to test the participants’ adherence to the weight management
program, and to compare the outcomes of the two different weight loss program delivery
methods.

Assessments

All participants will be required to attend regular clinical appointments for a duration
of approximately 15 min, as follows: at baseline, at weeks 6 and 12, and then again
for a follow-up appointment at week 24. Prior to each appointment, participants will
complete a Three-Day Food Record and selection of questionnaires to monitor compliance
and address some of the secondary outcome measures. The Bouchard Three-Day Physical
Activity Record 44] will be used to measure of total physical activity. The Three-Factor Eating Questionnaire
(TFEQ) 45] will provide a measure of dietary restraint, disinhibition and hunger, and will also
be used here to assess changes in satiety. The Self-Efficacy Scale 46] will be used to assess changes to participants’ self-efficacy. The WHO Quality of
Life Questionnaire 47] will be used to determine changes in participants’ quality of life. The short version
of the Depression Anxiety Stress Scale (DASS 21) 48] will be used to measure changes in general psychological wellbeing. The Self-Control
(Brief) Scale 49] will be used to provide an understanding of participants’ impulse control as it relates
to eating behaviour. The Diet and Physical Activity Survey, constructed using the
Theory of Planned Behaviour 50], will be used to determine participants’ intentions with regard to the dietary and
physical activity guidelines being used in the trial. The Survey of Weight Management
Program has some general questions regarding the ease of use of the dietary and physical
activity guidelines being utilized; there will be an extra section for Facebook Group
participants to assess the preferred device for accessing the weight management information
provided on Facebook. For Facebook Group participants only, the Social Media Survey
will be used to assess participants’ attitudes to social media. The final questionnaire
will also be administered to Facebook Group participants only; the Facebook Intensity
and Network Density Scales contains a combination of questions used in previous social
media research 51], 52]. It will be adapted for this study to assess the degree to which participants make
use of Facebook, as well as the strength and frequency of the social interactions
within the Facebook Group. In addition, the Facebook Group page will be printed at
the end of each week to corroborate self-reported Facebook usage data and monitor
participants’ online behaviour. Participants will be given questionnaires (including
the Food Record and Physical Activity Record) at each clinic appointment, according
to their group allocation. [For further information regarding the assessments please
see Table 1: Schedule of Assessments.] Participants will be instructed to use their participant
identification number only when completing all documents relating to this trial 42].

Table 1. Schedule of assessments

At each clinical appointment, weight will be recorded in light clothing without shoes.
(UM-018 Digital Scales; Tanita Corporation, Tokyo, Japan). Body composition will be
measured by bioelectrical impedance analysis (BIA) in light clothing without shoes
using the digital scales just mentioned. Height will be measured without shoes to
the nearest 0.1 cm using a wall-mounted stadiometer (26SM 200 cm SECA, Hamburg, Germany).
Height and weight measurements will be used to calculate participants’ BMI. Waist
circumference will be measured in the standing position at the narrowest area between
the lateral lower rib and the iliac crest; hip circumference will be measured at the
widest area across the buttocks. Briefly, fasting blood glucose will be taken using
the Accu-Chek® Performa glucometer and lancing device (Roche, Australia). Blood pressure
will be assessed with an automated, calibrated sphygmomanometer (Dinamap, Compact
T, Critikon, Germany). Pulse contour analysis (PCA) will be used to assess arterial
stiffness using the Pulse Trace PCA 2 (CareFusion, NSW, Australia). In addition, at
weeks 0 and 12 participants will be required to attend a local pathology collection
centre (PathWest Laboratory Medicine, Western Australia) for blood tests to measure
lipids (triglycerides (TG), total cholesterol (TC), low density lipoprotein (LDL)
and high density lipoprotein (HDL)) and insulin. [For further information regarding
the assessments please see Table 1: Schedule of Assessments.]

Statistical analysis

Based on a three group study with repeated measures, a sample size of 96 achieves
80 % statistical power to detect a medium to large effect size (Cohen’s d?=?0.4); that is, a difference of 6 kg between the two intervention groups, with alpha
set at 0.05. To allow for an attrition rate of 20 %, a total of 120 participants will
be recruited; i.e. 40 participants per group. Stratified randomisation will be used
to ensure that each group is matched in age and gender. The results will be analysed
using a mixed repeated measures analysis of variance (ANOVA) design. Data will be
expressed as mean (±SEM) and assessed for normality to ensure that the assumptions
of the analysis are met. If significant between groups effects are present, post hoc
analysis will be conducted using the Least Significant Difference (LSD) method. Statistical
significance will be considered at p??0.05. All statistical analyses will be performed
using SPSS 21.0 for Windows (SPSS Inc., Chicago, IL), and conducted using the participant
identification number only 42].