2.1 Study registration
The review's methods have been defined in advance following the Prepared Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines;this protocol has been formulated in accordance with the PRISMA-P checklist.
The study has been registered on the PROSPERO (https:// www.crd. york.ac.uk /PROSPERO/), the registration number is CRD42023470864
2.2. Study inclusion and exclusion criteria
Only studies that present original data will be considered for inclusion in the review. We will include studies that had to be population-based and reported the risk factors and prevalence of nAMD.
2.2.1.Types of studies. Inclusion: (1) Randomized controlled trial; (2) cohort studies; (3) case-control studies;(4) cross-sectional studies. Exclusion: (1) Literature not written in Chinese or English; (2) Research data that is incomplete or missing; (3) Original documents that cannot be obtained; (4) Duplicate publications of literature; (5) Editorials; (6) Commentaries.
2.2.2. Types of participants. Any study that includes at least one participant with nAMD.
2.2.3. Risk factors. age, male gender, genetic factors, smoking, cardiovascular diseases, surgery, total cholesterol [TC], triglyceride [TG], body mass index [BMI], systolic blood pressure [SBP].
2.2.4. Types of outcomes measures. Incidence and prevalence, risk factors of nAMD.
2.3. Search scheme and strategy
The following databases were searched: PubMed, Cochrane Library, Web of Science, Embase, OVID MEDLINE, China National Knowledge Infrastructure (CNKI), Wanfang, Chinese Biomedicine Literature Database (CBM-SinoMed) and VIP. Our comprehensive search strategies combined terms of diabetic retinopathy, epidemiology (incidence, prevalence, morbidity, mortality, epidemiology).The literatures will be searched from the establishment of the database to September 21, 2023, with "Macular Degeneration", "Retinal Degeneration","Choroidal Neovascularization", "prevalen*" and "Risk Factors"and so on were used as keywords for the search. The specific search strategy is presented in Table 1 (PubMed was used as an example). To supplement the electronic database search, reference lists of eligible publications and related reviews were also scanned to identify other potentially pertinent studies. No language restrictions were imposed on searches or search results.
Table 1 Search strategy used in PubMed database.
Number
|
Search terms
|
#1
|
"Macular Degeneration"[Mesh]
|
#2
|
(((((((((((Macular Degeneration[Title/Abstract]) OR (Maculopathy[Title/Abstract])) OR (Maculopathies[Title/Abstract])) OR (Macular Dystrophy[Title/Abstract])) OR (Macular Dystrophies[Title/Abstract])) OR (Age-Related Macular Degeneration[Title/Abstract])) OR (Age Related Macular Degeneration[Title/Abstract])) OR (Age-Related Macular Degenerations[Title/Abstract])) OR (Age-Related Maculopathies[Title/Abstract])) OR (Age Related Maculopathies[Title/Abstract])) OR (Age-Related Maculopathy[Title/Abstract])) OR (Age Related Maculopathy[Title/Abstract])
|
#3
|
#1 OR #2
|
#4
|
"Retinal Degeneration"[Mesh]
|
#5
|
retinal degeneration[Title/Abstract]
|
#6
|
#4 OR #5
|
#7
|
"Choroidal Neovascularization"[Mesh]
|
#8
|
"Retinal Drusen"[Mesh]
|
#9
|
"Macula Lutea"[Mesh]
|
#10
|
#7 OR #8 OR #9
|
#11
|
((((Choroidal Neovascular[Title/Abstract]) OR (Choroidal Neovascularization[Title/Abstract])) OR (exudative[Title/Abstract])) OR (degener*[Title/Abstract])) OR (Choroid Neovascularization[Title/Abstract])
|
#12
|
((((macul*[Title/Abstract]) OR (retina*[Title/Abstract])) OR (choroid*[Title/Abstract])) OR (wet[Title/Abstract])) OR (degener*[Title/Abstract])
|
#13
|
(((macul*[Title/Abstract]) OR (retina*[Title/Abstract])) OR (choroid*[Title/Abstract])) AND (neovasc*[Title/Abstract])
|
#14
|
(maculopath*[Title/Abstract]) OR (drusen*[Title/Abstract])
|
#15
|
((macul*[Title/Abstract]) AND (lutea*[Title/Abstract])) OR (syndrome[Title/Abstract])
|
#16
|
(macul*[Title/Abstract]) AND (dystroph*[Title/Abstract])
|
#17
|
((macul*[Title/Abstract]) OR (geographic*[Title/Abstract])) AND (atroph*[Title/Abstract])
|
#18
|
((AMD[Title/Abstract]) OR (ARMD[Title/Abstract])) OR (nAMD[Title/Abstract])
|
#19
|
((retina*[Title/Abstract]) AND (angiomat*[Title/Abstract])) AND (prolif*[Title/Abstract])
|
#20
|
#3 OR #6 OR #10 OR #11 OR #12 OR #13 OR #14 OR #15 OR #16 OR #17 OR #18 OR #19
|
#21
|
acid mine drainage
|
#22
|
#20 NOT #21
|
#23
|
"Risk Factors"[Mesh]
|
#24
|
(risk factor[Title/Abstract]) OR (risk)
|
#25
|
#23 OR #24
|
#26
|
"Epidemiologic Studies"[Mesh]
|
#27
|
(((((((((prevalen*[Title/Abstract]) OR (Inciden*[Title/Abstract])) OR (Percent*[Title/Abstract])) OR (epidemiol*[Title/Abstract])) OR (frequenc*[Title/Abstract])) OR (occurrenc*[Title/Abstract])) OR (morbidit*[Title/Abstract])) OR (rate*[Title/Abstract])) OR (Probabilit*[Title/Abstract])) OR (Population*[Title/Abstract])
|
#28
|
#26 OR #27
|
#29
|
#22 AND #25 AND #28
|
2.4. Study selection
Studies retrieved from the different data sources will be grouped together and duplicated records will be removed using a reference management software package (EndNote 2020, Clarative Analytics). Identified studies will be independently reviewed for eligibility by two authors (LJ, GD) in a two-step process; a first screen will be performed based on title and abstract while full texts will be retrieved for the second screen. At both stages intercoder agreement will be assessed using Cohens’ k. A minimum k value of 0.75 will be taken to represent high agreement[p]. Disagreements between reviewers will be resolved by discussion and consultation with a third author (WY), irrespectively of the k value. The studies’ selection process will be graphically reported in a PRISMA flow diagram[q].
2.5. Data extraction
With a predefined data-collection form, data will be extracted by one author (GE) supervised by a second author (XZL) using a standardised data extraction spreadsheet. The following information was extracted from the included studies:1) Characteristics of the study: authors’ names and affiliations, publication year, country of publication, study design, study period, study year, study setting and location, geographic region and so on.
2) Characteristics of the sample (general population and people with nAMD): sample size, sampling method, demographic characteristics of study participants (age, gender, ethnicity, etc), duration of nAMD, age (age range, mean or median age), gender (male, female or mixed);
3) Prevalence data: the number of people with nAMD and the number of participants who had been tested for nAMD, by age, nAMD duration, gender, setting;
4) Risk factor data: other behavioural and clinical risk factors (ie, smoking habits, BMI, blood pressure, lipid profile, current use of medications), OR and corresponding confidence intervals (CIs).
2.6. Risk of bias assessment
The quality assessment of the included studies will be conducted using three different assessment tools and two reviewers will independently assess the quality of included studies.(1)The ROBINS-I (Risk Of Bias In Non-randomised Studies - of Interventions), specifically developed for NRS I (Non-randomised studies of the effects of interventions)[r].The seven domains of the ROBINS-I tool were categorized as having low, moderate, serious, or critical risk of bias, or having no available information. After the evaluation of the seven domains, the overall Risk of Bias (RoB) for each study was assessed. (2) A Briggs Institute’s critical appraisal checklist is a specific method for assessing the quality of studies reporting prevalence data to be included in systematic reviews and meta-analysis[s]. The Joanna Briggs Institute’s checklist will be used as a reference when conducting sensitivity analysis restricted to high quality studies and, as recently proposed by Tracey et al[t], methodological quality will be considered ‘low’, ‘moderate’ and ‘high’ if three or less, four to six, and seven to nine criteria will be met, respectively. (3) The Cochrane bias risk assessment tool was used to evaluate the final included RCTs: random allocation method; allocation plan concealment; blinding of research subjects and experimenters; blinding of outcome evaluators; completeness of result data; selective reporting of studies Results; other sources of bias, including potential bias related to the specific research design of the study[u].For each of the above items, make a judgment of “low risk of bias”, “high risk of bias” and “uncertain risk of bias”. Disagreement will be solved by discussion or by consulting the third person (SLS).
2.7. Data synthesis
We will perform descriptive analysis and report the characteristics of included studies in summary tables and narrative text. Statistical analysis was performed on the extracted data using Stata 12.0 software. For measurement data, the weighted mean difference (WMD) is used as the combined effect size; for binary variable data, the odds ratio (OR) is used as the combined effect size.
2.8 Assessment of heterogeneity
To test the heterogeneity of the combined literature, we can use the statistics I2 and P values. If P≥0.1, I2<50%, it indicates that there is homogeneity among the studies or the heterogeneity is within an acceptable range. In this case, the fixed effects model can be used to calculate the effect size for merging the data. On the other hand, if P<0.1, I2>50%, it suggests the there is heterogeneity between the studies. In such cases, additional methods like Egger's method and Begg's method can be employed to assess publication bias.
2.9 Assessment of reporting biases
An assessment of reporting bias will be conducted to validate the study findings. If the number of included studies is greater than 10, the symmetry of the funnel plot will be evaluated using Begg and Egger tests with the aid of Stata 14.0 software.
2.10 Subgroup analysis
If there is considerable heterogeneity observed across the studies included in our analysis, we conducted subgroup analyses to further investigate potential factors influencing the results. These factors may include age, gender, race, treatment duration, sample size, disease classification, and other relevant variables. If substantial evidence is available, we subgroup analyses to examine the impact of specific factors on the results.