Evidence Mapping and Quality Analysis of Systematic Reviews on Various Aspects Related to Cleft Lip and Palate

Abstract

Background: Management of cleft lip and palate is interdisciplinary. An evidence-mapping approach was envisaged to highlight the existing gaps in this field, using only the highest level of evidence.

Objectives: To conduct evidence mapping and quality analysis of systematic reviews and meta-analyses related to any aspect of cleft lip and palate.

Search methods: The cleft lip and palate field was divided into 9 domains and 50 subdomains and a method of categorization of systematic reviews was established. A comprehensive search strategy was carried out in seven databases along with the search of gray literature and references of included articles.

Selection criteria: Systematic reviews related to any aspect of cleft lip and palate, conducted by a minimum of two reviewers, with a comprehensive search strategy and adequate quality analysis were included.

Data collection and analysis: A self-designed, pre-piloted data-extraction sheet was used to collect information that was analyzed through an expert group discussion. Quality analysis was performed using ROBIS-I, AMSTAR 2, and the PRISMA checklist.

Results: A total of 144 systematic reviews published between 2008 and 2022 were included. The largest number of these could be categorized in the therapeutic domain (n = 58). A total of 27% of the studies were categorized as inconclusive, 40% as partially conclusive, and 33% as conclusive. As per ROBIS-I, 77% of reviews had high risk of bias while 58% were graded as critically low in quality as per AMSTAR 2. The majority of systematic reviews showed low reporting errors.

Conclusions: The majority of systematic reviews related to cleft lip and palate relate to therapeutic and prognostic domains and show high risk of bias and critically low quality regardless of the source journal. The results of this paper might serve as a starting point encouraging authors to carry out high-quality research where evidence is lacking.

Registration: A multidisciplinary expert-group formulated an a priori protocol, registered in Open Science Framework (DOI 10.17605/OSF.IO/NQDV2).

Keywords: cleft lip and palate; evidence mapping; evidence-based medicine; risk of bias; systematic reviews.

Figure 1

Basis of categorization of domains and subdomains.

Figure 2

PRISMA 2020 flowchart including searches of databases, registers, and other sources.

Figure 3

Visual map showing the relationship of domains and subdomains with each other using VOS viewer software. Co-occurrence (proportionate to the size of the circle) represents the number of studies including the particular domain and subdomain, whereas the link strength (thickness of the connecting line between two domains and/or subdomains) represents the association between connected circles. The diagrammatic representation uses various colors and circles representing various domains and subdomains. (A) co-occurrence and link strength between domains and subdomains; (B) link strength of the therapeutic domain with other domains and subdomains, (C) link strength of the epidemiologic domain with other domains and subdomains.

Figure 4

Abacus evidence mapping (EM) plot showing risk of bias of systematic reviews as per ROBIS-I, with three blocks representing low, unclear, and high risk of bias on the y-axis, and domain on the x-axis. Within each block, the articles are represented by white and black beads with a unique identification number for each article. These numbers are the same as provided in the table describing their characteristics and across other supplementary material. These beads are arranged according to the year of publication. Black beads represent studies that were registered in PROSPERO or similar registries while white beads represent unregistered studies.

Figure 5

Abacus evidence mapping (EM) plot showing quality of systematic reviews as per AMSTAR 2, with four blocks representing critically low, low, moderate, and high grades in ascending order on the y-axis, and domain on the x-axis. Within each block, the articles are represented by white and black beads with a unique identification number for each article. These numbers are the same as provided in the table describing their characteristics and across other supplementary material. These beads are arranged according to the year of publication. Black beads represent studies that were registered in PROSPERO or similar registries while white beads represent unregistered studies.