Table 1 Inclusion/exclusion criteria
Evidence characteristics/Level of triage | Inclusion | Exclusion | Justification |
|---|---|---|---|
At level 1 (first screening or title and abstract screening)/level 2 (selection based on full text or full-text screening) | |||
Language | The study is published in English or possibly in French | The study is published in a language other than English or French | Data collection will be extended to French language publications to contribute to address possible publication bias. But this systematic review project does not have the resources to translate into languages other than English or French |
Year of publication | The study is published before 2024 | The study is published after 31 December 2023 | An increasing body of research recognises the involvement of environmental determinants in the risk of developing type 2 diabetes (T2D). This situation illustrates the global awareness of the need to promote neighbourhoods conducive to healthy living behaviours to achieve complete well-being |
Sources of evidence | - The study was published in a peer-reviewed journal - The study was published in one of the grey literature sources of the Laval University Libraries | Public interest reports or magazines or popular magazines are to be excluded | Although peer review is an essential safeguard of the scientific process, in this research, it is recognised that grey literature sources are a means of addressing potential publication bias |
Study design | The study may be experimental or non-experimental (cross-sectional, cohorts/longitudinal, case–control) or quasi-experimental (cohorts/longitudinal, case–control), with the aim to explain and quantify the relationship between T2DM (Outcome) and environmental determinants (exposure) using one risk estimator such as Risk ratio (RR), hazard ratio (HR) or odds ratio (OR) | The study uses a qualitative or mixed observational survey methodology | Qualitative data do not quantify the contribution of environmental determinants or objectively compare studies with each other |
Exposure(s) | The study analyses the correlation, contribution or influence or impact of exposure to local food landscape or built environment or deprivation or rural or urban cultural norms of organization and use of space | The study does not address the contribution, influence, or impact of exposure to environmental determinants | This is an indispensable aspect of answering the research question |
Comparator(s) | Evidence from control groups made up of individuals who may or may not be predisposed to the risk of T2DM or who are not permanently exposed to an unhealthy environment during their life course (men versus women, urban population vs rural population, unhealthy lifestyle behaviours and obese vs normal weight individuals) will be taken into account | Absence of comparator(s) | Subgroups may be used to improve knowledge of the nature of the relationship observed in this systematic review |
Main outcome(s) | The study seeks to explain the risk of type 2 diabetes mellitus (causal or correlational) | The study does not seek to explain the risk of type 2 diabetes mellitus | This is an indispensable aspect of answering the research question. Risk was chosen for two reasons: firstly, this systematic review is more concerned with explanatory analyses; secondly, according to exploratory research, it is the most widely used statistical measure of association in studies in this field |
Participants | Diabetic and nondiabetic individuals 18Â years of age or older | Individuals under the age of 18 are included in the study population | Dysfunction in insulin production often appears in adulthood. It is therefore recognized that for environmental characteristics to have an impact on lifestyle behaviors, one must have been exposed to them in the life course at least until adulthood |
Measure(s) of intervention, exposure | At least one indicator of rural or urban perception of organization and use of space or local food landscape or built environment or deprivation is being defined | There is no definition of environmental indicators | This is an indispensable aspect of answering the research question |
Measure(s) outcome | At least one indicator of type 2 diabetes (prevalence, incidence for descriptive analyses and risk ratio (RR), hazard ratio (HR), or odds ratio (OR) for explanatory analyses) is being defined (using fasting blood glucose level or FBG and 2-h plasma glucose level or 2hPG level; glycated haemoglobin level or HbA1c; insulin and homoeostatic model assessment of insulin resistance level or HOMA-IR or simply based on administrative health data (for example, the codes E110 to E119 in the 10th revision of International Statistical Classification of Diseases and Related Health Problems or ICD-10) or self-reported cases validated by a concordance study published) | The studied measure of association between DMT2 and the environment is not a risk estimator | Type 2 diabetics account for 90–95% of Mellitus diabetes cases worldwide. This is an indispensable aspect of answering the research question. Risk was chosen for two reasons: First, the systematic review is more concerned with explanatory analyses of DMT2; second, based on exploratory research, it is the most widely used statistical measure of association in studies in this field of research |