Logistic regression model for BPD as a function of Birth Weight

Study of Low Birth Weight Infants

 

The GENMOD Procedure

 

Model Information

Data Set

WORK.LOWBWT

Distribution

Binomial

Link Function

Logit

Dependent Variable

bpd

Observations Used

223

 

Response Profile

Ordered
Value

bpd

Total
Frequency

1

1

76

2

0

147

 

PROC GENMOD is modeling the probability that bpd='1'.

 

Criteria For Assessing Goodness Of Fit

Criterion

DF

Value

Value/DF

Deviance

221

223.7206

1.0123

Scaled Deviance

221

223.7206

1.0123

Pearson Chi-Square

221

251.6647

1.1388

Scaled Pearson X2

221

251.6647

1.1388

Log Likelihood

 

-111.8603

 

 

Algorithm converged.

 

Analysis Of Parameter Estimates

Parameter

DF

Estimate

Standard Error

Wald 95% Confidence Limits

Chi-Square

Pr > ChiSq

Intercept

1

4.0343

0.6958

2.6706

5.3980

33.62

<.0001

weight

1

-0.4229

0.0641

-0.5485

-0.2973

43.55

<.0001

Scale

0

1.0000

0.0000

1.0000

1.0000

 

 

 

NOTE:

The scale parameter was held fixed.