Table 2 Relationship between depressive, manic, and total morbidity index and several characteristics of illness course (Wald tests for significance of fixed effects and covariates)

Total morbidity index

 Year of treatment; df = 19

19.847

0.404

 Year of treatment × group membership interaction; df = 19

17.658

0.545

 Number of episodes before index; df = 1

0.602

0.438

 Number of recurrences before index; df = 1

0.002

0.963

 Latency between onset of illness and start of lithium treatment; df = 1

1.991

0.158

Depressive morbidity index

 Year of treatment; df = 19

26.112

0.127

 Year of treatment × group membership interaction; df = 19

12.208

0.877

 Number of episodes before index; df = 1

0.304

0.581

 Number of recurrences before index; df = 1

0.773

0.379

 Latency between onset of illness and start of lithium treatment; df = 1

2.778

0.096

Manic morbidity index

 Year of treatment; df = 19

22.963

0.239

 Year of treatment × group membership interaction; df = 19

16.271

0.639

 Number of episodes before index; df = 1

0.305

0.581

 Number of recurrences before index; df =1

2.105

0.147

 Latency between onset of illness and start of lithium treatment; df = 1

0.013

0.908