Table 5.
Prevalence Rates (per 1,000) of Individual Diagnoses within Fetal Alcohol Spectrum Disorders and Total FASD by Three Methods of Estimation from Rural ZA Communities
| Oversample of children ≤ 25th centile on height, weight, or OFC |
Random Sample Rate and Estimated Cases in the Non- Consented Children (n=406) |
Combined rate from consented sample (n=1354) and estimated cases in non- consented sample (n=512) |
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|---|---|---|---|---|---|---|---|---|---|---|---|
| Diagnosis | (a) n |
Enrolled rate1 (n=1866) |
Consented rate2 (n=1354) |
n | Proportion of FASD cases in random sample |
(b) Estimated cases in non- consented sample (n=512) |
Rate of FASD from random sample only3 |
95% Confidence Interval |
(a + b) Total estimated cases (n=1866) |
Estimated rate for all enrolled students4 |
95% Conference Intervals |
| FAS | 173 | 92.7 | 127.7 | 51 | .1256 | 64 | 125.6 | 96.4 to 153.6 | 237 | 127.0 | 111.9 to 142.1 |
| PFAS | 109 | 58.4 | 80.5 | 41 | .1009 | 52 | 100.9 | 75.4 to 127.7 | 161 | 86.2 | 73.5 to 99.0 |
| ARND | 59 | 31.6 | 43.5 | 21 | .0517 | 26 | 51.7 | 31.8 to 69.8 | 85 | 45.6 | 36.1 to 55.0 |
| Total FASD | 341 | 182.7 | 251.8 | 113 | .2783 | 142 | 278.3 | 238.5 to 316.1 | 483 | 258.9 | 238.9 to 278.7 |
Denominator is all children attending first grade in local schools. Rate per 1,000 based on the entire enrollment in 1st grade classrooms (n=1866).
Denominator is the total number of children with consent to participate in this study. Rate per 1,000 based on the sample consented and screened (n=1354).
Calculated as the FASD cases diagnosed from the randomly-selected control candidates (numerator) over the total number of randomly-selected children x 1,000.
Rate per 1,000 children calculated from FASD cases diagnosed in the consented sample (a) added to the estimated cases in the non-consented sample utilizing the proportional diagnostic distribution of FASD cases among randomly-selected children (b), and divided by all 1st grade children enrolled in the schools (n=1866).