Table 2.

Means of the Five Clusters on the 12- and 24-Month MDI Scores, the 3- or 4-Year IQ Scores, and the 5- or 6-Year IQ Scores for Total Sample of Very Low Birth Weight Children (≤1500 g)*

TestTotal
(N = 203)
A.
Average–
Stable
(N = 27)
B.
Average–
Declined to
Low Average
(N = 48)
C.
Average–
Declined to
Below Average
(N = 88)
D.
Very Low–
Increased to
Low Average
(N = 16)
E. Very
Low–
Stable
(N = 24)
MDI-1291.09  ± 20.06100.3  ± 18.7110.4  ± 8.691.9  ± 8.463.2  ± 9.057.9  ± 10.1
MDI-2482.90  ± 17.59109.6  ± 11.890.5  ± 10.279.4  ± 9.977.1  ± 7.454.3  ± 7.9
IQ 3/482.59  ± 14.55102.9  ± 12.188.2  ± 9.378.8  ± 9.184.4  ± 5.561.3  ± 9.9
IQ 5/685.30  ± 15.36107.0  ± 10.789.9  ± 12.482.0  ± 8.787.9  ± 8.062.0  ± 10.0
Percentage correct89.7%92.6%93.8%81.8%100%100%
 classification
  • * All children in the sample were tested at each age. Group differences were tested by one-way ANOVAs, all P = .000; results of posthoc LSD procedures for MDI12: Cluster B > A, C, D, E; Cluster A > C, D, E; Cluster C > D, E; MDI24: Cluster A > B, C, D, E; Cluster B > C, D, E; Clusters C, D > E; IQ 3/4: Cluster A > B, C, D, E; clusters B, D > C, E; Cluster C > E; IQ 5/6: Cluster A > B, C, D, E; Clusters B, D > C, E; Cluster C > E.

  • Predicted group membership from discriminant analysis using the four test scores as discriminators.