Effectiveness of Web-Based Self-Disclosure Peer-to-Peer Support for Weight Loss: Randomized Controlled Trial

Background Obesity is one of the most common public health problems in the industrialized world as a cause of noncommunicable diseases. Although primarily used for one-on-one communication, email is available for uninterrupted support for weight loss, but little is known about the effects of dietitian group counseling for weight control via the Internet. Objective We developed a Web-based self-disclosure health support (WSHS) system for weight loss. This study aims to compare the effect of weight change between those using the WSHS and those using the email health support (EHS). Methods This study was designed as an open prospective individual randomized controlled trial. Eligible participants were aged 35 to 65 years with a body mass index (BMI) of ≥25.0 in their latest health examination. Participants were randomly assigned to either the WSHS group or the EHS group. Thirteen registered dietitians under the direction of a principal dietitian each instructed 6 to 8 participants from the respective groups. All participants in the WSHS group could receive nutritional advice and calculate their nutritive intake from a photograph of a meal on their computer screen from the Internet sent to them by their dietitian, receive supervision from the registered dietitian, and view fellow participants’ weight changes and lifestyle modifications. In the EHS group, a participant could receive one-on-one nutritional advice and calculate his/her nutritive intake from the photograph of a meal on computer screen sent by email from his/her dietitian, without being able to view fellow participants’ status. The follow-up period was 12 weeks for both groups. The primary outcome measure was change in body weight. The secondary outcome measure included changes in BMI and waist circumference. The intergroup comparison of the changes before and after intervention was evaluated using analysis of covariance. Results A total of 193 participants were randomly assigned to either the WSHS group (n=97) or the EHS group (n=96). Ten from the WSHS group and 8 from the EHS group dropped out during the study period, and the remaining 87 in the WSHS group and 88 in the EHS group were followed up completely. Weight loss was significantly greater in the WSHS group than in the EHS group (–1.6 kg vs –0.7 kg; adjusted P=.04). However, there were few differences in waist circumference between the 2 groups. (–3.3 cm vs –3.0 cm; adjusted P=.71). Conclusions Our newly developed WSHS system using forced self-disclosure had better short-term weight loss results. Further study in a longer-term trial is necessary to determine what effects this type of intervention might have on long-term cardiovascular disease. Trial Registration University Hospital Medical Information Network Clinical Trial Registration (UMIN-CTR): UMIN000009147; https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function=brows&action=brows&type=summary&recptno=R000010719&language=E (Archived by WebCite at http://www.webcitation.org/6HTCkhb1p).


INTRODUCTION 2a-i) Problem and the type of system/solution
Obesity is one of the most common public health problems in the industrialized world as a cause of noncommunicable diseases such as ischemic heart disease and diabetes mellitus [1,2]. This study aimed to compare the weight loss between the WPS and the conventional e-mail health support (EMS). 2a-ii) Scientific background, rationale: What is known about the (type of) system A study reported that people were more likely to gain weight when obese persons were around them [3]. In a similar way, behavior modification for weight loss might also 'transmit' to others if a person makes an effort to lose weight. In addition, the necessity to enhance the motivation for weight loss by group dynamics in nutritional counseling has been emphasized [4,5]. In nutritional counseling for weight loss, face-to-face support that takes into consideration the individual's background and personal characteristics is generally conducted by registered dietitians [6,7]. Recently, e-mails, which are mainly for one-to-one communication, have been frequently used for weight loss [8][9][10][11][12][13]. METHODS 3a) CONSORT: Description of trial design (such as parallel, factorial) including allocation ratio This study aimed to compare the weight loss between the WPS and the conventional e-mail health support (EMS) . Our hypothesis is that weight loss would be greater in the WPS group than in the EMS group. 3b) CONSORT: Important changes to methods after trial commencement (such as eligibility criteria), with reasons None. 3b-i) Bug fixes, Downtimes, Content Changes 4a) CONSORT: Eligibility criteria for participants Men and women aged 35-65 years with a body mass index (BMI) of 25.0 or more from their latest health examination were eligible. Persons who agreed to participate in our study were invited to an initial face-to-face guidance interview. At this interview, those who had been receiving dietary and exercise therapies, or who could not access Internet or e-mail, or who had a current BMI less than 24.5, were excluded from our intervention. 4a-i) Computer / Internet literacy 4a-ii) Open vs. closed, web-based vs. face-to-face assessments: This study was an open prospective individual randomized controlled trial. This study aimed to compare the weight loss between the WPS and the conventional e-mail health support (EMS). For this study, we recruited participants by mail, contacting clients of the Kyoto University Health Service, Japan, urging them to obtain nutritional counseling for weight loss. 4a-iii) Information giving during recruitment 4b) CONSORT: Settings and locations where the data were collected The Kyoto University Health Service, Japan. 4b-i) Report if outcomes were (self-)assessed through online questionnaires None. 4b-ii) Report how institutional affiliations are displayed 5) CONSORT: Describe the interventions for each group with sufficient details to allow replication, including how and when they were actually administered 5-i) Mention names, credential, affiliations of the developers, sponsors, and owners 5-ii) Describe the history/development process 5-iii) Revisions and updating 5-iv) Quality assurance methods 5-v) Ensure replicability by publishing the source code, and/or providing screenshots/screen-capture video, and/or providing flowcharts of the algorithms used 5-vi) Digital preservation

5-vii) Access
The WPS group members were given a personal account and password, and could freely access the WPS system ( Figure 1). Each participant set his/her own handle name and target body weight at the beginning. 5-viii) Mode of delivery, features/functionalities/components of the intervention and comparator, and the theoretical framework All members were requested to fill in their present body weight and their level of lifestyle modification attained, along with their motivation level, which were expressed in a three-level scale (good [○], fair [△], and poor [×]), on the screen of the individual's system web page every week. Participants received nutritional advice and had their nutritive intakes calculated by their dietitians using a photograph of a meal. A participant and his/her dietitian could discuss their questions and comments in this personal area. 5-ix) Describe use parameters 5-x) Clarify the level of human involvement 5-xi) Report any prompts/reminders used The WPS group members wereexpressed in a three-level scale (good [○], fair [△], and poor [×]), on the screen of the individual's system web page every week.
The EMS group members were provided with a Microsoft Excel file.They could send questions and receive nutritional advice and photo-based nutritive intakes by e-mail. 5-xii) Describe any co-interventions (incl. training/support) The WPS group members were given a personal account and password, and could freely access the WPS system ( Figure 1). Each participant set his/her own handle name and target body weight at the beginning. All members were requested to fill in their present body weight and their level of lifestyle modification attained, along with their motivation level, which were expressed in a three-level scale (good [○], fair [△], and poor [×]), on the screen of the individual's system web page every week. Participants received nutritional advice and had their nutritive intakes calculated by their dietitians using a photograph of a meal. A participant and his/her dietitian could discuss their questions and comments in this personal area.
In this system, group members could view their fellow participants' weight changes (not actual values) and their related conditions. A participant and his/her dietitian could put their queries or comments on the participant's individual screen, but the fellow participants could not write down in this column.
The EMS group members were provided with a Microsoft Excel file. They set their target body weight loss at the beginning, and subsequently filled in their present body weight, their levels of lifestyle modification attainment, and their motivation level, similar to the WPS group members. They could send questions and receive nutritional advice and photo-based nutritive intakes by e-mail. However, they could not obtain information on their fellow participants' health status. After 12 weeks of online health support, the participants were asked to come in for remeasurement of their height, weight, waist circumference, and QOL by the same dietitian they saw at the beginning of the study. 6a) CONSORT: Completely defined pre-specified primary and secondary outcome measures, including how and when they were assessed The primary outcome measure was change in body weight. The secondary outcome measure included changes in BMI, waist circumference, and QOL.
The comparison of changes before and after intervention between the groups was evaluated using analysis of covariance adjusted for sex, age, and the baseline value of the corresponding item at the first guidance interview. All statistical analyses were performed using JMP® 9 statistical software (SAS Institute, Inc, Cary, NC.). All tests were 2-tailed, and P values of <.05 were considered statistically significant. 6a-i) Online questionnaires: describe if they were validated for online use and apply CHERRIES items to describe how the questionnaires were designed/deployed 6a-ii) Describe whether and how "use" (including intensity of use/dosage) was defined/measured/monitored 6a-iii) Describe whether, how, and when qualitative feedback from participants was obtained 6b) CONSORT: Any changes to trial outcomes after the trial commenced, with reasons None. 7a) CONSORT: How sample size was determined 7a-i) Describe whether and how expected attrition was taken into account when calculating the sample size 7b) CONSORT: When applicable, explanation of any interim analyses and stopping guidelines None. 8a) CONSORT: Method used to generate the random allocation sequence The participants were randomly assigned to either the WPS group or the EMS group using the minimization method, balancing sex (male or female), age (<40 years or =>40 years), and baseline body weight (<60 kg, 60-80 kg, or =>80 kg) by one of the authors(MA). Then they were assigned a counselor-dietitian. A total of thirteen registered dietitians under the direction of a principal dietitian provided nutritional counseling. Each dietitian was allocated to both one of the WPS group and one of the EMS group, with six to eight participants of a group being supported by one assigned dietitian during the study period. The follow-up period was 12 weeks for both groups. 8b) CONSORT: Type of randomisation; details of any restriction (such as blocking and block size) The participants were randomly assigned to either the WPS group or the EMS group using the minimization method, balancing sex (male or female), age (<40 years or =>40 years), and baseline body weight (<60 kg, 60-80 kg, or =>80 kg) by one of the authors(MA). Then they were assigned a counselor-dietitian. 9) CONSORT: Mechanism used to implement the random allocation sequence (such as sequentially numbered containers), describing any steps taken to conceal the sequence until interventions were assigned The participants were randomly assigned to either the WPS group or the EMS group using the minimization method, balancing sex (male or female), age (<40 years or =>40 years), and baseline body weight (<60 kg, 60-80 kg, or =>80 kg) by one of the authors(MA). Then they were assigned a counselor-dietitian. 10) CONSORT: Who generated the random allocation sequence, who enrolled participants, and who assigned participants to interventions The participants were randomly assigned to either the WPS group or the EMS group using the minimization method, balancing sex (male or female), age (<40 years or =>40 years), and baseline body weight (<60 kg, 60-80 kg, or =>80 kg) by one of the authors(MA). Then they were assigned a counselor-dietitian. 11a) CONSORT: Blinding -If done, who was blinded after assignment to interventions (for example, participants, care providers, those assessing outcomes) and how 11a-i) Specify who was blinded, and who wasn't None. This study was an open prospective individual randomized controlled trial. 11a-ii) Discuss e.g., whether participants knew which intervention was the "intervention of interest" and which one was the "comparator" 11b) CONSORT: If relevant, description of the similarity of interventions The WPS group members were given a personal account and password, and could freely access the WPS system ( Figure 1). Each participant set his/her own handle name and target body weight at the beginning. All members were requested to fill in their present body weight and their level of lifestyle modification attained, along with their motivation level, which were expressed in a three-level scale (good [○], fair [△], and poor [×]), on the screen of the individual's system web page every week. Participants received nutritional advice and had their nutritive intakes calculated by their dietitians using a photograph of a meal. A participant and his/her dietitian could discuss their questions and comments in this personal area.
In this system, group members could view their fellow participants' weight changes (not actual values) and their related conditions. A participant and his/her dietitian could put their queries or comments on the participant's individual screen, but the fellow participants could not write down in this column.
The EMS group members were provided with a Microsoft Excel file. They set their target body weight loss at the beginning, and subsequently filled in their present body weight, their levels of lifestyle modification attainment, and their motivation level, similar to the WPS group members. They could send questions and receive nutritional advice and photo-based nutritive intakes by e-mail. However, they could not obtain information on their fellow participants' health status. After 12 weeks of online health support, the participants were asked to come in for remeasurement of their height, weight, waist circumference, and QOL by the same dietitian they saw at the beginning of the study. 12a) CONSORT: Statistical methods used to compare groups for primary and secondary outcomes We conducted intention-to-treat analyses in this study. All data are expressed as mean ± SD. BMI was defined as the weight (kg) over height (m) squared. Baseline characteristics were compared between the groups using unpaired t-test for numerical variables and chi-square test for categorical variables. The comparison of changes before and after intervention between the groups was evaluated using analysis of covariance adjusted for sex, age, and the baseline value of the corresponding item at the first guidance interview. All statistical analyses were performed using JMP® 9 statistical software (SAS Institute, Inc, Cary, NC.). All tests were 2-tailed, and P values of <.05 were considered statistically significant. 12a-i) Imputation techniques to deal with attrition / missing values We conducted intention-to-treat analyses in this study. All data are expressed as mean ± SD. BMI was defined as the weight (kg) over height (m) squared. Baseline characteristics were compared between the groups using unpaired t-test for numerical variables and chi-square test for categorical variables. The comparison of changes before and after intervention between the groups was evaluated using analysis of covariance adjusted for sex, age, and the baseline value of the corresponding item at the first guidance interview. All statistical analyses were performed using JMP® 9 statistical software (SAS Institute, Inc, Cary, NC.). All tests were 2-tailed, and P values of <.05 were considered statistically significant. 12b) CONSORT: Methods for additional analyses, such as subgroup analyses and adjusted analyses We conducted intention-to-treat analyses in this study. All data are expressed as mean ± SD. BMI was defined as the weight (kg) over height (m) squared. Baseline characteristics were compared between the groups using unpaired t-test for numerical variables and chi-square test for categorical variables. The comparison of changes before and after intervention between the groups was evaluated using analysis of covariance adjusted for sex, age, and the baseline value of the corresponding item at the first guidance interview. All statistical analyses were performed using JMP® 9 statistical software (SAS Institute, Inc, Cary, NC.). All tests were 2-tailed, and P values of <.05 were considered statistically significant. RESULTS 13a) CONSORT: For each group, the numbers of participants who were randomly assigned, received intended treatment, and were analysed for the primary outcome A total of 196 participants were recruited for this trial from July 2008 through February 2009. Among them, three participants with a BMI<24.5 at the first guidance interview were excluded, and the remaining 193 were randomly assigned to either the WPS group (97) or the EMS group (96). Ten persons from the WPS group and eight persons from the EMS group dropped out during the study period, leaving 87 in the WPS group and 88 in the EMS group to complete the study (Figure 2). 13b) CONSORT: For each group, losses and exclusions after randomisation, together with reasons Ten persons from the WPS group and eight persons from the EMS group dropped out during the study period, leaving 87 in the WPS group and 88 in the EMS group to complete the study (Figure 2). 13b-i) Attrition diagram 14a) CONSORT: Dates defining the periods of recruitment and follow-up Carried out from July 2008 through February 2009. 14a-i) Indicate if critical "secular events" fell into the study period 14b) CONSORT: Why the trial ended or was stopped (early) None. 15) CONSORT: A table showing baseline demographic and clinical characteristics for each group Baseline characteristics of the participants are shown in Table 1. Mean age was 50 years, and mean body weight was around 78 kg in both groups. There were no significant differences in sex ratio, BMI, waist circumference, target body weight loss, or QOL levels between the groups. 15-i) Report demographics associated with digital divide issues Baseline characteristics of the participants are shown in Table 1. Mean age was 50 years, and mean body weight was around 78 kg in both groups. There were no significant differences in sex ratio, BMI, waist circumference, target body weight loss, or QOL levels between the groups. 16a) CONSORT: For each group, number of participants (denominator) included in each analysis and whether the analysis was by original assigned groups 16-i) Report multiple "denominators" and provide definitions A total of 196 participants were recruited 16-ii) Primary analysis should be intent-to-treat 17a) CONSORT: For each primary and secondary outcome, results for each group, and the estimated effect size and its precision (such as 95% confidence interval) Differences in changes of outcomes between the WPS group and EMS group are shown in Table 2. The loss in body weight was significantly greater in the WPS group than in the EMS group (-1.6 kg versus -0.7 kg, adjusted P=.038). The decrease in BMI was also greater in the WPS group than in the EMS group (-0.6 versus -0.3, adjusted P=.051). However, there were no significantly different changes in waist circumference. Changes in QOL scores, general health perception, vitality, role functioning related to physical and emotional problems, and mental health, were not significantly different between the groups, either. 17a-i) Presentation of process outcomes such as metrics of use and intensity of use 17b) CONSORT: For binary outcomes, presentation of both absolute and relative effect sizes is recommended None. 18) CONSORT: Results of any other analyses performed, including subgroup analyses and adjusted analyses, distinguishing pre-specified from exploratory None. 18-i) Subgroup analysis of comparing only users 19) CONSORT: All important harms or unintended effects in each group None.(Health intervention study) 19-i) Include privacy breaches, technical problems 19-ii) Include qualitative feedback from participants or observations from staff/researchers DISCUSSION 20) CONSORT: Trial limitations, addressing sources of potential bias, imprecision, multiplicity of analyses 20-i) Typical limitations in ehealth trials This study has some inherent limitations. First, the WPS system is limited to those who can use a personal computer. Smart phones and tablet devices are currently available, and we will develop a modified WPS system that works on these devices. Second, we only observed the effect on weight loss. The true end point of nutritional counseling should be the reduction in mortality and morbidity from cardiovascular diseases. Weight loss could prevent cardiovascular events [36]. Therefore, we consider that weight change is reasonable as a short-term index. 21) CONSORT: Generalisability (external validity, applicability) of the trial findings 21-i) Generalizability to other populations 21-ii) Discuss if there were elements in the RCT that would be different in a routine application setting 22) CONSORT: Interpretation consistent with results, balancing benefits and harms, and considering other relevant evidence 22-i) Restate study questions and summarize the answers suggested by the data, starting with primary outcomes and process outcomes (use) We developed the WPS system, which is capable of activating group dynamics, and evaluated its effectiveness in controlling body weight in a randomized controlled trial. In this trial, the WPS yielded participants with a significantly greater weight loss than did the conventional EMS. 22-ii) Highlight unanswered new questions, suggest future research Other information 23) CONSORT: Registration number and name of trial registry Clinical Trial Registration Information: http://www.umin.ac.jp/ctr/index-j.htm UMIN000009147 24) CONSORT: Where the full trial protocol can be accessed, if available This study was approved by the Ethics Committee of Kyoto University Graduate School of Medicine. 25) CONSORT: Sources of funding and other support (such as supply of drugs), role of funders None. X26-i) Comment on ethics committee approval All procedures were conducted according to the Declaration of Helsinki. Participants submitted their written informed consent prior to participation. This study was approved by the Ethics Committee of Kyoto University Graduate School of Medicine. x26-ii) Outline informed consent procedures X26-iii) Safety and security procedures X27-i) State the relation of the study team towards the system being evaluated