The study was conducted in two steps to develop and validate the Egyptian developmental screening chart (EDSC) from January 2019 till January 2020 in Egypt. Institutional Review Boards (IRB) of the Menoufia faculty of medicine had approved the study (ID: 180112Ped). Written consent was obtained from parents/or guardians who were informed about the objective of the study, its benefits and the absence of any risk associated with the participation of their children.
Step 1: Instrument Development:
A cross sectional randomized study was implemented on 1503 normally developed Egyptian children aged from birth up to 30 months at vaccination centers and well-baby clinics. A minimal sample size of 1500 children was calculated as enough required sample to conduct the trial assuming a significance level of 95% (α=0.05), and statistical power (1 – β) of 80%.17-18 The sample size was calculated according to Charan and Biswas (2013).19 Online Open Source Epidemiologic Statistics for Public Health was also used to confirm the calculation. 20
A total number of 1600 children were enrolled in the study. Exclusion criteria were applied to 97 children leaving 1503 children as a final total sample to be included in the study. The selected children were divided into 30 groups based on their chronological age (CA) (44 to 58 child per each age group).
- Inclusion and Exclusion Criteria
The study sample was complied to inclusion and exclusion criteria. children should be full term,
age from birth up to 30 months, anthropometric measurements (weight, length/ height and head
circumference) within normal for age according to WHO growth charts.21 Exclusion criteria included; history of prematurity, hospital admission including neonatal intensive-care unit (NICU), low socioeconomic level, malnourished baby according to WHO (≤-2 standard deviation of weight to length/ height), chronic diseases (cardiac, hematological, chest or endocrine diseases) and developmental or physical disabilities.
- Milestones and chart development.
EDSC checklist based on BDST questionnaire. BDST questionnaire consists of 54 items 22 motor (gross and fine motor) and 32 mental (cognitive, social and language). These items were chosen carefully from Bayley scale of infants which consist of 230 items (67 motor and 163 for mental development). Milestones arranged from 0 to 30 months of age in an ascending order. Our research team discussed the cultural appropriateness of Baroda items and translated it to Arabic. Then items were simplified to the parents/or guardians with their local expressions till parents/or guardians could easily understand and answer unequivocally. A workshop training was provided to the field work team to explain the items in the checklist and how to interview with the parents/or guardians. A pilot study of 150 children was designed (five children per month) to test all items of the developmental checklist for Egyptian children and also to test and standardize the capabilities of the involved team before proceeding to the main data collection. The pilot study concluded that the data collector team were able to understand and apply the items, parents were apple to understand and answer questions easily with yes or no, items didn’t return with missing answers and there was a certain degree of variability in most of items.
The scores of checklist items passed by children were analyzed and tabulated. 97% pass level of developmental scores of children was taken as a reference. The 50% and 97% level age placement of each item were plotted against its corresponding CA of children and then smoothed into two curves. Any child score below 97% pass level considered delayed.
A z-score chart for motor and mental development follow up was designed also by calculating each age group achievement.
- Measurements and Data Collection
Socioeconomic and demographic factors were collected using Fahmy schedule which is used for estimating socioeconomic standard in Egypt. 22 Low socioeconomic status was excluded as it has a negative environmental influence on child development, for example; malnutrition can influence development by causing him or her to fuss more or play less and affect brain development function23, also Poverty and social-cultural factors increase both physiological and behavioral deficits. 24
Children were examined for any developmental or physical disability. Weight, recumbent length (for less than 24 months), height (from 24 month to 30 months) and head circumference (HC) were measured. Weight was measured by (LAICA model bf 2051, Italy) till the age of 2 years then another scale (Beurer model GS 11, Germany) was used till age of 30 month. The length of children was measured by a recumbent baby length scale. The height was measured by Harpenden fixed stadiometer. HC was measured by flat metal tape. This is followed by an interview to their parents/or guardians to complete the developmental checklist.
Step 2: Validation of EDSC
A validation study to EDSC was done against ASQ-3 as a gold standard tool.11 A different sample of 337 children were enrolled in a cross sectional randomized study from vaccination centers and well-baby clinics. A sample size of 299 children was calculated as enough required sample to conduct this agreement study, assuming that all individual but one pair agree with each other.25 A total number of 345 children were enrolled in the study. Exclusion criteria were applied to 8 children leaving 337 children as a final total sample. The selected children were divided into 15 groups based on their CA (first 15 age groups in the ASQ-3) ranging from 2 to 30 months. Children suffered from acute severe illness or previously diagnosed with a developmental disorder were excluded.
EDSC checklist was applied to the parents/or guardians and the score was calculated by one of our team work. After obtaining informed consent, a detailed clinical evaluation was done. 97% pass level is determined as a cut off point, any child failed to pass above the 97% criterion was defined as ‘delayed”. ASQ-3 was also applied to the same participants as a reference standard by another observer in our team who was blinded to the results of EDSC. ASQ-3 questionnaire contains 30 questions for each specific age group. These questions examine five domains: Fine Motor, Gross Motor, Communication, Problem-Solving and Personal-Social; each domain includes 6 questions that can be answered with a yes (10 points), sometimes (5 points) or not yet (0 points), as well as nine open-ended questions. Scores falling in the white area indicate the child is developing typically. Scores falling in the gray area mean the child should be monitored and another screening may be needed later on. Scores falling in the black area (cut off point) mean that the child may be at risk for developmental delay and should be referred for further assessment (2 SD below mean).
Statistical analysis
Data were collected and entered to the computer using SPSS (Statistical Package for Social Science) program for statistical analysis (ver 21).26 Data were entered as numerical or categorical, as appropriate and described using minimum, maximum, mean, standard deviation. Categorical variables were described using frequency and percentage. Comparisons were carried out between two studied dependent (developmental age of the Egyptian children on 50% and 97% pass levels using Baroda curve vs the developmental age of the same child using EDSC) normally distributed variables using paired t-test.27A Z-score was calculated for each age group at the following: - 3, -2, -1, 0,1,2,3 equally in sequence the percentiles (0.2nd, 2.3rd, 16th, 50th, 84th, 97.7th, 99.8th respectively).28 Polynomial trend line curves were used by Microsoft Excel (Microsoft Office Professional).29
Validation evaluation was carried out using MedCalc Software version 14. 30 The following tests were carried out: Sensitivity (true positive rate), Specificity, positive and negative predictive value as well as accuracy.31 Kappa values interpretations 0.75 considered as excellent, 0.40 to 0.75 as fair to good, and below 0.40 as poor according to fleiss's equally arbitrary guidelines. 32 An alpha level was set to 5% with a significance level of 95%.