Classification of the SRS population according to the NH-CSS and statistical comparison of the two clinical groups
| Likely-SRS (≥4 factors present) | Unlikely-SRS (≤3 factors present) | p Value | |
|---|---|---|---|
| Mean or Freq. | Mean or Freq. | ||
| Mean of factors recorded ‘yes’ for each group (subjects with missing data excluded)*† | 5.29 (n=52) | 2.89 (n=9) | 0.000 |
| SGA (birth weight and/or birth length)ठ| 55 of 60 (91.67%) | 7 of 9 (77.78%) | NS |
| Postnatal growth failureठ| 55 of 58 (94.83%) | 7 of 9 (77.78%) | 0.07 (NS) |
| Relative macrocephaly at birthठ| 46 of 56 (82.14%) | 2 of 9 (22.22%) | 0.000 |
| Protruding foreheadठ| 55 of 58 (94.83%) | 5 of 9 (55.56%) | 0.000 |
| Body asymmetryठ| 44 of 60 (73.33%) | 1 of 9 (11.11%) | 0.000 |
| Feeding difficulties and/or BMI≤−2SDS | 58 of 59 (98.31%) | 3 of 9 (33.33%) | 0.000 |
*t Test, equal variances not assumed; t=15.279; df 27.619; Sig (2-tailed) 0.000.
†Only subjects with data for all 6 factors were included in this ‘overall’ top-level analysis, to ensure that group mean factor numbers were comparable.
‡Pearson's χ2 test.
§The Ns for each scoring system factor can be less than the total of 60, because some subjects were missing data for one or more factors (but still had enough data to qualify for ‘4 or more factors recorded as yes’).
NH-CSS, Netchine-Harbison clinical scoring system; NS, not significant; SGA, small for gestational age; SRS, Silver-Russell syndrome.