PR O T O C O L Open Access
Weight maintenance interventions for
people with type 2 diabetes mellitus: a
systematic review protocol
Sarah Sauchelli
*
, Julia Bradley, Jennifer Cox, Clare England and Rachel Perry
Abstract
Background: Weight loss maintenance is a challenge for people with type 2 diabetes mellitus (T2DM), which
attenuates the long-term benefits of weight loss for diabetes management. Medication, specific dietary
requirements and the psychosocial burden of T2DM signify that weight loss maintenance designed for obesity may
not suit people with T2DM. The primary objective of this review is to comprehensively evaluate existing weight
maintenance interventions for people with or at high risk of T2DM.
Methods: We registered a protocol for the systematic review and meta-analysis of randomised and non-
randomised weight maintenance interventions for T2DM. Studies included will have been carried out in adults with
clinical diagnosis of T2DM or pre-diabetes. All intervention types will be accepted (e.g. behavioural/lifestyle change
and pharmacological). The primary outcomes will be weight control, glycaemic control and adverse effects.
Secondary outcomes will include cardiovascular risk factors (e.g. total cholesterol, LDL-cholesterol, blood pr essure
control), psychological wellbeing (including health-related quality of life), change in glucose medication and waist
circumference. Multiple electronic databases will be searched such as MEDLINE, EMBASE, Web of Science,
PsychINFO and international registers (e.g. Cochrane Central Register of Controlled Trials, WHO ICTRP). OpenGrey
will be searched for grey literature. Two researchers will screen all citations and abstracts. This process will also be
conducted by an additional researcher using a semi-automated tool to reduce human error. Full-text articles will be
further examined by the researchers to select a final set for further analysis, and a narrative synthesis of the
evidence will be presented. Potential sources of heterogeneity will be assessed, and a meta-analysis will be
conducted if feasible. Risk of bias will be evaluated using the Cochrane risk of bias tool and the certainty of
evidence using the GRADE (grading of recommendations, assessment, development and evaluation) approach.
Discussion: This review will critically appraise existing weight maintenance interventions targeting T2DM. Findings
will inform future intervention development to support people with T2DM delay weight regain and prolong
successful diabetes management.
Systematic review registration: PROSPERO CRD42020168032
Keywords: Weight maintenance, Type 2 diabetes, Systematic review
© The Author(s). 2020 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License,
which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give
appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if
changes were made. The images or other third party material in this article are included in the article's Creative Commons
licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons
licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain
permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the
data made available in this article, unless otherwise stated in a credit line to the data.
* Correspondence: sarah.sauc[email protected]
National Institute for Health Research Bristol Biomedical Research Centre,
University Hospitals of Bristol and Weston NHS Foundation Trust and
University of Bristol, Level 3, University Hospitals Bristol Education and
Research Centre, Upper Maudlin Street, Bristol BS2 8AE, UK
Sauchelli et al. Systematic Reviews (2020) 9:210
https://doi.org/10.1186/s13643-020-01467-7
Background
The International Diabetes Federation reports that in
2019 approximately 463 million adults between ages 20
and 79 were living with diabetes mellitus, with projec-
tions estimating a rise to 700 million by 2045 [1]. The
existence of multiple comorbidities and an augmented
risk of mortality have placed diabetes mellitus as a global
health and development challenge [1]. More than 90% of
people with diabetes mellitus have type 2 diabetes melli-
tus (T2DM). Although a genetic pred isposition results in
an increased susceptibility among some individuals, ex-
cess weight, due to poor diet and insu fficient physical
activity, is the key modifiable risk factor [2]. Hence, life-
style change to maintain a healthy weight is a fundamen-
tal component of existing prevention and management
strategies [3].
Extensive literature shows that lifestyle interventions,
particularly those focusing on diet control, enable weight
loss, ameliorate cardiometabolic health and HbA1c con-
trol [47]. More recently, it has been demonstrated that
a very low-calorie diet encouraging weight loss enables
some people with T2DM reach a remission-like state
[8]. However, the majority of people with T2DM strug-
gle to maintain the weight lost once weight loss inter-
ventions have ended [9]. At 12-month follow-up, the
intervention benefits for weight, HbA1c levels, lipids and
blood pressure are less clear [10]. There is also some evi-
dence that weight loss maintenance is short-lived in
people with T2DM compared to non-diabetic people
with obesity [11] or people at high risk [6].
The primary target for diabetes manageme nt is glu-
cose control [3] and commonly used pharmacological
treatments for glucose regulation facilitate weight gain
[3, 12]. Medication used to treat psychiatric comor-
bidities and diabetes-related medical complications
can have a similar side effect [13, 14]. The specific
dietary requirements and the psychosocial burden of
diabetes self-management can also influence adher-
ence to physical activity and dietary guide lines among
this clinical group [15]. Behavioural interventions
shown to be beneficial for weight loss maintenance in
obesity [16, 17] may therefore not be equally applic-
able to people who additionally have T2DM.
The prescription of weight maintenance programmes
is among the American Diabetes Associations recom-
mendations for medical care in diabetes [18]. Further, 4-
year weight maintenance (< 5% change from baseline
measure), particularly when combined with glycaemic
control, has been found to result in a reduction in med-
ical costs, compared to a 14% increase when weight gain
occurs alongside an incremental increase in mean A1C
levels [19]. Given the importance of weight maintenance
for diabetes-related health outcomes and the economic
savings for the healthcare system, development and
implementation of weight maintenance interventions
that are effective for people with or at high risk of
T2DM is crucial. Comprehensive reviews on interven-
tion effectiveness are fundamental for evidence-based
decision-making in clinical practice [20]. Yet, interven-
tions focusing on weight maintenance for people with
T2DM are yet to be systematically summarised and
assessed for quality.
Aims
The systematic review described in this protocol aims to
thoroughly evaluate the effectiveness of existing weight
maintenance interventions that have targeted people
with or at high risk of T2DM. It will consider glucose
regulation and weight as primary outc omes, in order to
discern features of current interventions that may aid
patients adhere to treatment targets and to identify chal-
lenges to be addressed by novel interventions.
A second objective of this review is to further evaluate
the applicability of text-mining tools and machine learn-
ing to support clinical systematic reviews. As the rate of
publication rises across disciplines, evide nce synthesis is
becoming increasingly more time-consuming [21]. Auto-
mated tools/processe s may reduce workload for re-
searchers. However, the use of varied terminology to
define medical phenomena and clinical interventions
often requires complex decision-making that may be dif-
ficult to predict prior to screening. Therefore, the trad-
itional systematic review screening process will be
carried out in parallel to a protocol using automated ap-
proaches to identify where human judgement may be
needed when conducting systematic reviews of studies
evaluating clinical interventions.
Methods
The present study protocol is reported in accordance with
the reporting guidance provided in the Preferred Report-
ing Items for Systematic Reviews and Meta-Analyses Pro-
tocols (PRISMA-P) statement [22] (Additional file 1). This
protocol has been registered in the International Prospect-
ive Register of Systematic Reviews (PROSPERO) database
(registration ID: CRD42020168032).
Eligibility criteria
Both published and unpublished studies including a
weight maintenance intervention will be analysed. Stud-
ies will be included irrespective of the country where
they have been carried out, year of publication and the
language of the report. Studies may be both randomised
and non-randomised, and blinding is not required given
that it is not always possible in behav ioural interven-
tions. The use of the findings from this review to de-
velop a novel intervention and design a randomised
controlled trial justify the inclusion of non-randomised
Sauchelli et al. Systematic Reviews (2020) 9:210 Page 2 of 7
studies [23]. Studies meeting the following criteria will
be deemed eligible for analysis (PICO structure).
Population
Participants will be adults (age 18 years), with a clinical
diagnosis of T2DM or pre-diabetes according to the cri-
teria of the World Health Organisation [24] or equivalent
international standards [25]. When it is unclear whether a
diagnosis was conducted, the study authors will be con-
tacted to obtain the information. Further, studies where
participants display impaired fasting glucose or non-
diabetic hyperglycaemia will also be included. Participants
will additionally have had to achieve weight loss within 24
months prior to the start of the weight maintenance inter-
vention or have been instructed to maintain their weight
as a preventative measure. No restriction will be placed on
the amount of weight loss achieved during a weight loss
programme given differential targets and success rates
across studies [26]. Participants may have been recruited
from the general community, hospital, clinical care centre
or other health services. Exclusion criteria include individ-
uals with overweight or obesity who do not have a diagno-
sis of pre-diabetes or T2DM, individuals with type 1
diabetes mellitus and individuals with conditions requiring
antipsychotic drugs.
Intervention
Behaviour change and lifestyle interventions (e.g. with a
focus on promoting physical activity and healthier eating
habits) will be included, along with pharmacological
treatments (e.g. lipase inhibitors such as orlistat) and nu-
trition therapies targ eting the modification of nutrient or
whole-food intake (as defined by the American Diabetes
Association [27];). Pharmacological treatments must be
approved as a weight loss drug by a regu latory agency
(e.g. European Medicines Agency or UK Medical Medi-
cines & Healthcare products Regulatory Agency), and
food supplements to complement the normal diet must
adhere to the definition provided by the Food and Drug
Administration on food supplements (see: https://www.
fda.gov/food/information-consumers-using-dietary-sup-
plements/questions-and-answers-dietary-supplements).
Both stand-alone and combined interventions will be in-
cluded, and any delivery approach for the non-
pharmacological interventions will be accepted (e.g.
face-to-face, online, as part of an education programme).
Papers will be excluded if the intervention focuses solely
on weight loss or the weight loss component is not
clearly distinguished from the weight maintenance
phase. Further, studies that use Ephedra as a supplement
will be excluded as it is banned in both the European
Union and by the Food and Drug Administration, as
well as those using Chinese traditional medic ine or
Ayurvedic medicine where there are no details of active
ingredients/herbs utilised.
Control/comparator
Single-cohort studies will be accepted, as well as studies
where the comparator is no intervention, standard or
minimal care, waitlist or the use of a placebo. When the
details of the information are unclear, authors will be
contacted to provide further information.
Outcomes
Primary outcomes will be those most important to pa-
tients receiving the interventions. These are weight
maintenance, glycaemic control (as indicated by one or
more of the following: HbA1c, fasting plasma glucose,
insulin sensitivity/resistance) and adverse effects. As
there is no current consensus on a definition for weight
maintenance, we will focus on weight difference between
baseline and at least one post-intervention measurement.
Adverse effects will be the physical and/or psychological
side effects that may emerge from the intervention (e.g.
disordered eating behaviour).
Secondary outcomes will include cardiovascular risk
factors (e.g. total cholesterol, low-density lipoprotein
cholesterol, high-density lipoprotein cholesterol, triacyl-
glycerol, diastolic blood pressure, systolic blood pres-
sure), psychological wellbeing (including health-related
quality of life), change to glucose medication and waist
circumference. Quantitative (both continuous and cat-
egorical) outcomes will be considered.
Should amendments be necessary, these shall be docu-
mented, reported and fully justified.
Information sources and search strategy
A systematic search of research conducted up to the
date of search initiation will be carried out. This includes
searching the following databases (no restriction on pub-
lication status):
1. MEDLINE and PreMEDLINE (OvidSP) (1950 to
date)
2. EMBASE Classic + EMBASE (OvidSP) (1974 to
date)
3. PsycINFO (OvidSP) (1806 to date)
4. CENTRAL (The Cochrane Library)
5. ISI Web of Science: Science Citation Index
Expanded (SCIEXPANDED) (1900 to date)
6. ISI Web of Science: Conference Proceedings
Citation Index-Science (1990 to date)
7. International trial registers (World Health
Organisation International Clinical Trials Registry
portal and ClinicalStudyResults.org)
Sauchelli et al. Systematic Reviews (2020) 9:210 Page 3 of 7
We will additionally conduct hand searches of refer-
ence lists and relevant systematic reviews, and we will
review the grey literature (e.g. conference papers/confer-
ence proceedings, theses, dissertations, studies published
in non-indexed journals) via OpenGrey. Personal letters
and e-mails will be sent to the corresponding authors of
papers in the field of weight management in T2DM. The
authors will be asked for information regarding unpub-
lished or ongoing studies.
Search terms identified for each of the following relevant
categories: population (type 2 diabetes or diabetes melli-
tus or diabet es mell itus type 2 or pre-diabetes or pr edi-
abetes or hyperglycaemia), intervention (weight
maintenance or maintained weight or weight mainte-
nence AND behav* or lifestyl e* or online or com-
puter or web or pharma* or food repla* or *supple*),
and outcome (weight or body mass index or BMI or
glycaemic* control or cardiovascular*
or psych*). Bool-
ean searches will be carried out with terms combining cat-
egories and variations of the terms (via truncation). Medical
Subject Headings (MeSH) keywords and Emtree keywords
will be used. The draft search strategy for MEDLINE is pre-
sented in an additional file (Additional file 2).
Screening and data extraction
The search will be managed using the Rayyan (http://
rayyan.qcri.org) software app [28]. Results will be
imported into Rayyan, which automatically detects du-
plicates. Duplicates will also be detected through the
manual data screening process. We will seek information
regarding the outlined PICOs.
Two reviewers will independently screen all titles and
abstracts identified by the search strategy based on the
inclusion criteria. Articles that appear to meet the inclu-
sion criteria will be extracted and reviewed in full by two
authors. Inconsistencies will be discussed, and if unre-
solved another member of the team will be brought in
to make the final decision. Studies deemed irrelevant will
be excluded, and reason will be provided. Authors of un-
published studies will be contacted.
Semi-automated screening
Search results will additionally be uploaded to
AbstrackR, a citation screening programme functioning
on an algorithmic framework that predicts the likelihood
citations are relevant for further inspection [29]. Screen-
ing will be initiated by two reviewers until the
programme indicates it is ready to make predictions. Ci-
tations extracted through this approach will be com-
pared and cross-checked against the output of the
manual screening and selection process. Precision, false-
negative rate, number of relevant citations missed and
researcher time saved will be examined to determine the
usefulness of AbstrackR.
Data extraction
Two revie wers will independently extract the data of the
included studies using a standardised data extraction
form shown in an additional file (Additional file 3). This
includes the following:
1. Publication details (authors, title, date of
publication, country of origin, funding source,
corresponding author conta ct details)
2. Study characteristics (setting, study design, number
of patients randomised to each group)
3. Participant characteristics (demographics, clinical
characteristics)
4. Intervention and comparator characteristics. These
will be prespecified for each type of intervention.
We will also extract information from all included
studies on the following factors: mode of delivery
(verbal, written, computer, phone app), place of
delivery, who delivered the intervention, duration of
the intervention, number of sessions and format
(individual or group).
5. Outcomes (as detailed in the previous section). We
will record the number of participants assessed for
each outcome, the mean values and standard
deviations (if available) or medians and interquartile
ranges for continuous data and any reported
summary statistics (e.g. effect estimates, CIs,
standard errors, ranges).
Inconsistencies in data extraction will be discussed
and recorded. If needed, a third author will be included
in the discussion to reach a final decision. When data is
missing or inadequately described, three attempts will be
made to request the information from the corresponding
author.
Data synthesis
A narrative synthesis of all included primary studies will
be conducted. We will prov ide information on patient
populations studied, the interventions evaluated, and any
comparators used; how the studies have described and
measured patient-important outco mes; and a brief sum-
mary of results in relation to weight maintenance, glu-
cose control and adverse effects from the intervention.
This will provide initial insight on study heterogeneity.
A more detailed quantitative summary of the data for
each study included will be reported in a separate table.
The table will show location where the study was con-
ducted, population demographics, interventions and
comparators, assessment time frame and outcomes (pri-
mary and secondary separate ly). An overall synthesis of
the data extracted will be provided in the form of forest
plots for each of the primary outcome variables. All re-
sults of both primary and secondary outcomes will be
Sauchelli et al. Systematic Reviews (2020) 9:210 Page 4 of 7
reported in a results table. Overall effect size on out-
come change between baseline and follow-up assess-
ments will be reported as weighed mean differences with
95% confidence intervals.
Meta-analyses will only be conducted if data from
three or more studies were available. We will attempt to
combine the results for studies that use similar interven-
tions and report similar outcomes. However, there is
likely to be heterogeneity in the types of participants, the
intervention and its delivery. We will therefore be using
random-effects meta-analysis models for our primary
analysis to pool data across trials, where study weighing
is based on in-study and between-study variances. How-
ever, fixed-effect meta-analysis models will also be ex-
plored. All meta-analyses will be carried out with the
Comprehensive Meta-Analysis software [30]. Clinical
heterogeneity between studies will be evaluated by iden-
tifying variability in participants, baseline data, interven-
tions and outcomes. The I
2
statistic will be calculated to
quantify and interpret statistical heterogeneity [31]. We
will apply the following thresholds for the interpretation
of the I
2
statistic: 0 to 40%, might not be important; 30
to 60%, may represent moderate heterogeneity; 50 to
90%, may represent substantial heterogeneity; and 75 to
100%, represents considerable heterogeneity [32].
Pooled risk ratios and 95% confidence intervals (CIs)
will be calculated for dichotomous outcomes. Pooled
mean differences and 95% CIs or standardised mean dif-
ferences and 95% CI will be calculated for continuous
outcomes when results are reported on the same scale
(or can be converted to the same scale), or if results are
reported on different scales, respectively. When available
data does not enable statistical pooling, results will be
reported in a narrative format.
Subgroup analyses
If there is enough data, subgroup analysis will be com-
pleted. We expect that some weight maintenance interven-
tions may have been attached to the end of a weight loss
programme, while others might be stand-alone. Factors that
contribute to weight regain is time lapse since weight loss
intervention [33]. Hence, effectiveness of weight mainten-
ance interventions may be differential if they were preceded
by a weight loss intervention or not. We will also compare
studies based on intervention type (e.g. diet vs combined
behavioural), intervention delivery format (e.g. face to face
vs online) and duration of intervention, given that these
characteristics have previously been linked to effectiveness
in weight loss interventions [3436].
Missing data
If data is not available in the format required, we will
first contact study authors or we will back-calculate the
data if possible (e.g. standard deviation from standard
errors or 95% CIs, mean and standard deviation from
median and range, etc.). Reasons for missing data will be
recorded (e.g. drop-outs, losses to follow-up and
withdrawals).
Risk of bias in individual studies
The Cochrane Risk of Bias Version 2 tool [37] will be
used for randomised controlled trials, while the
ROBINS-I tool [38] for observational studies. Two inde-
pendent reviewers will assess risk of bias using the rele-
vant tool. The latest version of the Cochrane risk of bias
tool (v2 [37];) assesses each study on the following 5
domains:
Domain 1: Risk of bias arising from the
randomisation process
Domain 2: Risk of bias due to deviations from the
intended interventions
Domain 3: Risk of bias due to missing outcome data
Domain 4: Risk of bias in measurement of the
outcome
Domain 5: Risk of bias in selection of the reported
result
Justification for decisions will be presented as supple-
mentary material.
Additional analyses
A sensitivity analysis will be conducted including only
studies classified as low risk of bias. Any studies that had
imputed results will be removed from the pooled ana-
lysis. Fixed effects meta-analyses will also be conducted.
Further, we expect to carry out at least one sensitivity
analysis to ensure robustness of conclusions from pooled
estimate against variation in the timing of outcome as-
sessment by eligible studies. Furth er sensitivity analyses
may be conducted if deemed necessary depending on
the studies identified from the search.
If over 10 studies are identified, a funnel plot will be
generated to assess further publication bias.
Confidence in cumulative evidence
The strength of the overall body of evidence for each
outcome will be assessed using the GRADE system [39]
(software: https:/ /gradepro.org/), after generating a sum-
mary of findings table. Grading will be carried out by
the team of reviewers. Grading will be based on risk of
bias of individual studies, inconsistency (based on vari-
ation in point estimates, confidence intervals overlap, p
value of heterogeneity, I
2
score, outcome of the sub-
group analysis), indirectness (based on differences in in-
terventions and patients, method of measurement of
patient-important outcomes and comparison of inter-
ventions), imprecision (based on Optimal Information
Sauchelli et al. Systematic Reviews (2020) 9:210 Page 5 of 7
Size, sample size, overlapping confidence intervals and
judgement on the importance of observed differences)
and publication bias (based on funding sources, size of
studies and the comprehensiveness of data search).
Discussion
Multiple weight loss interventions have been trialled
for people with T2DM, showing substantial benefits
for diabetes management [40]. Yet, weight rega in
shortly after the completion of a weight loss
programme is commo n in T2DM [11]. Cost-effective
interventions to prolong weight loss maintenance in
T2DM are urgently needed. This review will examine
the effectiveness of existing weight maintenance inter-
ventions for T2DM with t he scope to inform the de-
velopment of future interventions that are tailored to
the needs of this clinical population. By comparing
the step-by-step outputs of the systematic process
when conducted solely by researchers versus when
the review is supported by automated tools, we will
further ascertain the amount of t ime saved when
these tools are applied, as well a s identify where hu-
man input is required to achieve accuracy. We aim to
use the information to generate a standardised proto-
col that researchers can adhere to when employing
automated tools to conduct systematic reviews on
complex clinical interventions. A speedier critical ap-
praisal of the existing literature without compromis-
ing quality will accelerate the development process of
evidence-based interventions. However, a limitation of
using semi-automated tools to assist screening is that
these tools are highly reliant on there being enough
eligible studies for training the syste m. Hence,
though semi-automated tools are highly promising to
facilitate reviews with large datasets, they may be less
applicable with more systematic reviews targeting a
less explored field of research.
We also expect that this review may require
consultation with authors of candidate citations as it
is common for weight maintenance interventions t o
be incorporated as part of a larger weight l oss
programme [8]. Discussions with healthcare profes-
sionals and experts in the field suggest that we will
identify a limited number of studies, the interven-
tions evaluated are likely to vary and the assessment
of outcomes are likely to occur at distinct time
points in relation to the intervention (particularly at
follow-up). Further, behaviour change and lifestyle
interventionsnormallyaddressmultiplefactors(e.g.
psychological, behavioural and nutritional) to enable
weight maintenance. Characteristics associated with
intervention effectiveness will therefore be hard to
pinpoint and is likely to require in-depth analysis.
Additional limitations that we may find inclu de small
sample siz es or no justification for sample size, a
short f ollow-up in assessment and poor reporting of
or no explanation for attrition. Given the above, we
expect to find high h eterogeneity among the in-
cluded studies and the need for caution when inter-
preting the pooled results.
Amendments made to this protocol will be recorded
on PROSPERO and reported in the final review manu-
script in a table format.
Supplementary information
Supplementary information accompanies this paper at https://doi.org/10.
1186/s13643-020-01467-7.
Additional file 1. PRISMA-P 2015 Checklist. Table guiding reader to
guide the reader through the sections of the protocol depicting the
recommended items to be addressed by a systematic review.
Additional file 2. Draft Search Strategy. Document providing an
example of a search strategy to be used during the database search of
the systematic review.
Additional file 3. Data Extraction Form. Template to be used to extract
relevant data of all included studies.
Abbreviations
T2DM: Type 2 diabetes mellitus; PRISMA-P: Preferred Reporting Items for
Systematic Reviews and Meta-Analyses Protocols; PROSPERO: International
Prospective Register of Systematic Reviews; PICO: Population, intervention,
comparison and outcomes; CI: Confidence interval
Acknowledgements
We thank Dr Kazeem Olorisade (University of Bristol) for providing advice
regarding the use of semi-automated tools to assist screening during the
systematic review process. Preparation of this protocol was supported by the
NIHR Biomedical Research Centre at University Hospitals of Bristol and Wes-
ton NHS Foundation Trust and the University of Bristol. The views expressed
are those of the author(s) and not necessarily those of the NIHR or the De-
partment of Health and Social Care.
Authors contributions
The protocol was developed by all authors. SS is the guarantor of the review
and drafted the manuscript. JB, JC, CE, and RP provided edits for manuscript
improvement. The authors read and approved the final manuscript.
Funding
The review will form part of the research programme of the NIHR Biomedical
Research Centre at University Hospitals of Bristol and Weston NHS
Foundation Trust and the University of Bristol. No external funding will be
sought for completion. The NIHR was not involved in the development of
this protocol.
Availability of data and materials
Not applicable
Ethics approval and consent to participate
Not applicable
Consent for publication
Not applicable
Competing interests
The authors declare that they have no competing interests.
Sauchelli et al. Systematic Reviews (2020) 9:210 Page 6 of 7
Received: 3 May 2020 Accepted: 25 August 2020
References
1. International Diabetes Federation. IDF diabetes atlas, 9th edition. Brussels;
2019.
2. Zheng Y, Ley SH, Hu FB. Global aetiology and epidemiology of type 2 diabetes
mellitus and its complications. Nat Rev Endocrinol. 2018;14(2):8898.
3. Van Gaal L, Scheen A. Weight management in type 2 diabetes: Current and
emerging approaches to treatment. Diabetes Care. 2015;38(6):116172.
4. Johnson WD, Brashear MM, Gupta AK, Rood JC, Ryan DH. Incremental
weight loss improves cardiometabolic risk in extremely obese adults. Am J
Med. 2011;124(10):9318.
5. Wing RR, Lang W, Wadden TA, Safford M, Knowler WC, Bertoni AG, et al.
Benefits of modest weight loss in improving cardiovascular risk factors in
overweight and obese individuals with type 2 diabetes. Diabetes Care. 2011;
34(7):14816.
6. Sumamo Schellenberg E, Dryden DM, Vandermeer B, Ha C, Korownyk C.
Lifestyle interventions for patients with and at risk for type 2 diabetes: a
systematic review and meta-analysis. Ann Int Med. 2013;159:54351.
7. Huang XL, Pan JH, Chen D, Chen J, Chen F, Hu TT. Efficacy of lifestyle
interventions in patients with type 2 diabetes: a systematic review and
meta-analysis. Eur J Intern Med. 2016;27:3747.
8. Lean ME, Leslie WS, Barnes AC, Brosnahan N, Thom G, McC ombie L,
et al. Primary care-led weight management for remission of type 2
diabetes (DiRECT): an open-label, cluster-randomised tr ial. Lancet. 2018;
391(10120):54151.
9. Gage D. Weight loss/maintenance as an effective tool for controlling type 2
diabetes: novel methodology to sustain weight reduction. Diabetes Metab
Res Rev. 2012;28(3):2148.
10. Franz MJ, Boucher JL, Rutten-Ramos S, VanWormer JJ. Lifestyle weight-loss
intervention outcomes in overweight and obese adults with type 2
diabetes: a systematic review and meta-analysis of randomized clinical trials.
J Acad Nutr Diet. 2015;115(9):144763.
11. Guare JC, Wing RR, Grant A. Comparison of obese NIDDM and nondiabetic
women: short- and long-term weight loss. Obes Res. 1995;3(4):32935.
12. UK Prospective Diabetes Study (UKPDS) Group. Intensive blood-glucose
control with sulphonylureas or insulin compared with conventional
treatment and risk of complications in patients with type 2 diabetes (UKPDS
33). Lancet. 1998;352(9131):83753.
13. Cabrera J, Emir B, Dills D, Murphy TK, Whalen E, Clair A. Characterizing and
understanding body weight patterns in patients treated with pregabalin.
Curr Med Res Opin. 2012;28(6):102737.
14. Scheen AJ, De Hert MA. Abnormal glucose metabolism in patients treated
with antipsychotics. Diabetes Metab. 2007;33(3):16975.
15. Gonzalez JS, Tanenbaum ML, Commissariat PV. Psychosocial factors in
medication adherence and diabetes self-management: implications for
research and practice. Am Psychol. 2016;71(7):53951.
16. Dombrowski SU, Knittle K, Avenell A, Araújo-Soares V, Sniehotta FF. Long
term maintenance of weight loss with non-surgical interventions in obese
adults: systematic review and meta-analyses of randomised controlled trials.
BMJ. 2014;348:g2646.
17. Paixão C, Dias CM, Jorge R, Carraça EV, Yannakoulia M, Zwaan M, et al.
Successful weight loss maintenance: a systematic review of weight control
registries. Obes Rev. 2020;21(5):e13003.
18. American Diabetes Association. Standards of medical care in
diabetes2019 abridged for primary care providers. Diabetes Care. 2018;
42(SUPPL.1):S1194.
19. Nichols GA, Bell K, Kimes TM, OKeeffe-Rosetti M. Medical care costs
associated with long-term weight maintenance versus weight gain among
patients with type 2 diabetes. Diabetes Care. 2016;39(11):19816.
20. Bornmann L, Mutz R. Growth rates of modern science: a bibliometric
analysis based on the number of publications and cited references. J Assoc
Inf Sci Technol. 2015;66(11):221522.
21. Bastian H, Glasziou P, Chalmers I. Seventy-five trials and eleven systematic
reviews a day: How will we ever keep up? PLoS Med. 2010;7(9):e1000326.
22. Moher D, Shamseer L, Clarke M, Ghersi D, Liberatî A, Petticrew M, et al.
Preferred reporting items for systematic review and meta-analysis protocols
(PRISMA-P) 2015 statement. Syst Rev. 2015;4(1):1.
23. Reeves B, Deeks J, Higgins J, Wells G. Group on behalf of the CN-RSM.
Section 13.1.2 including non-randomized studies. In: Higgins JSG, editor.
Cochrane Handbook for Systematic Reviews of Interventions; 2011.
24. World Health O rganisation. Use of glyca ted haemoglobin (HbA1c) in
the diagnosis of diabetes mellitus abbreviated report of a WHO
consultation. 2011.
25. American Diabetes Association, et al. Diabetes C are. 2018;
41(Supplement 1):S1327.
26. Terranova CO, Brakenridge CL, Lawler SP, Eakin EG, Reeves MM.
Effectiveness of lifestyle-based weight loss interventions for adults with type
2 diabetes: a systematic review and meta-analysis. Diabetes Obes Metab.
2015;17(4):3718.
27. Evert AB, Dennison M, Gardner CD, Timothy Garvey W, Karen Lau KH, MacLeod
J, et al. Nutrition therapy for adults with diabetes or prediabetes: a consensus
report. Diabetes Care. American Diabetes Association Inc. 2019;42:73154.
28. Ouzzani M, Hammady H, Fedorowicz Z, Elmagarmid A. Rayyan-a web and
mobile app for systematic reviews. Syst Rev. 2016;5(1):210.
29. Rathbone J, Hoffmann T, Glasziou P. Faster title and abstract screening?
Evaluating Abstrackr, a semi-automated online screening program for
systematic reviewers. Syst Rev. 2015;4(80):17.
30. Blais MA. Comprehensive meta-analysis: a computer program for research
synthesis. J Pers Assess. 2003;80(3):3212.
31. Fletcher J. What is heterogeneity and is it important? Br Med J. 2007;
334(7584):8496.
32. Deeks JJ, Higgins JPTAD. Chapter 9: Analysing data and undertaking meta-
analyses. In: Higgins J, Green S, editors. Cochrane Handbook for Systematic
Reviews of Interventions Version 510 (updated March 2011); 2011.
33. Hall KD, Kahan S. Maintenance of lost weight and long-term management
of obesity. Med Clin North Am. W.B. Saunders. 2018;102:18397.
34. Ahern AL, Wheeler GM, Aveyard P, Boyland EJ, Halford JCG, Mander AP,
et al. Extended and standard duration weight-loss programme referrals for
adults in primary care (WRAP): a randomised controlled trial. Lancet. 2017;
389(10085):221425.
35. Johns DJ, Hartmann-Boyce J, Jebb SA, Aveyard P. Diet or exercise
interventions vs combined behavioral weight management programs: a
systematic review and meta-analysis of directcom parisons. J Acad Nutr
Diet. 2014 Oct 1;114(10):155768.
36. Sorgente A, Pietrabissa G, MauroManzoni G, Re F, Simpson S, Perona S, et al.
Web-based interventions for weight loss or weight loss maintenance in
overweight and obese people: a systematic review of systematic reviews,
vol. 19. J Med Int Rese: Journal of Medical Internet Research; 2017.
37. Sterne JAC, Savović J, Page MJ, Elbers RG, Blencowe NS, Boutron I, et al. RoB 2: a
revised tool for assessing risk of bias in randomised trials. BMJ. 2019;366:l4898.
38. Sterne JA, Hernán MA, Reeves BC, Savović J, Berkman ND, Viswanathan M,
et al. ROBINS-I: a tool for assessing risk of bias in non-randomised studies of
interventions. BMJ. 2016;355:i4919.
39. Guyatt G, Oxman AD, Akl EA, Kunz R, Vist G, Brozek J, et al. GRADE
guidelines: 1. Introduction - GRADE evidence profiles and summary of
findings tables. J Clin Epidemiol. 2011;64(4):38394.
40. Wilding JPH. The importance of weight management in type 2 diabetes
mellitus. Int J Clin Pract. 2014;68(6):68291.
PublishersNote
Springer Nature remains neutral with regard to jurisdictional claims in
published maps and institutional affiliations.
Sauchelli et al. Systematic Reviews (2020) 9:210 Page 7 of 7