Table 1 Comparing hospitalization rates during the influenza season and non-influenza season using different methods of defining the influenza season, 1986–87 to 1990–91.

5% Moving Average

Rate

11.39

10.52

1.08 (1.01–1.16)

Events, No.

1204

2177

Patient-days, No.

1057293

2069683

10% Moving Average

Rate

11.34

10.63

1.07 (0.99–1.15)

Events, No.

901

2480

Patient-days, No.

794239

2332737

First/Last

Rate

11.26

10.35

1.09 (1.01–1.16)

Events, No.

1777

1604

Patient-days, No.

1577740

1549236

5% Total Season

Rate

11.18

10.72

1.04 (0.96–1.13)

Events, No.

687

2694

Patient-days, No.

614407

2512569