65 The incidence of different forms of ileus following surgery for abdominal birth defects in infants Chapter 3 were read to determine eligibility for inclusion (LES,DN). If the full text was not found the authors were contacted. The reference lists of the included articles were cross checked to find additional articles. Validity and Eligibility assessment All included articles were assessed for the methodological quality and risk of bias. For cohort studies the Newcastle Ottawa quality assessment scale was used [32]. In randomized controlled trials this was done using the Jadad scoring system [33]. The assessment was done by LES and DN separately. Data synthesis For each complication and each disease in a study, a weighted average of the logit proportions was determined by the use of the generic inverse variance method. The logit proportions were back transformed to the summary estimate and 95%- CIs were obtained in a summary proportion representing the pooled proportion of the form of ileus. Heterogeneity was assessed using the I2 and χ2 statistics. Analyses were performed with the use of R-studio version 3.6.1 (package “meta” (Schwarzer, 2007) and “metaprop” (Viachtbauer, 2010)). The random-effects model was used for interpretation. Heterogeneity was deemed significant if the pooled data’s p value was <0.05 or χ2 statistics were ≥75. Heterogeneity was interpreted as small (I2≤0.25), medium (I2=0.25 – 0.50) or strong (I2≥0.50), according to Higgins [34]. Results Study characteristics In total, 5784 records were identified. After automated removal of duplicates, 3909 records were left for title and abstract screening. Of the 3909 records, 722 were included and assessed for full text. Following full text evaluation 152 studies were included for quantitative analysis (Figure 1). Of the 152 studies, 118 were retrospective cohort studies, 25 were prospective cohort studies, four were retrospective multicentre cohort studies, two were retrospective matched case-control studies, two were randomized controlled trials and one was a combined study of a prospective and retrospective cohort. Studies were conducted in 31 different countries. Asian countries were most prominent with 58 studies, European studies represented 41, North- & South-America represented 38, Africa represented 9, The Middle-East 4 and Oceania represented 2. Of the 152 studies, 86 (57%) reported a follow-up of at least half a year.
RkJQdWJsaXNoZXIy MTk4NDMw