Table 2 Rate ratios (RR) and 95 % CI for unadjusted and adjusted (age, sex, and additional covariates^a) models for all-age hospitalizations in the coal seam gas, coal high-impact, and rural low-impact study areas over time (1995–2011)^b

 All-cause

1.01 (1.00–1.01)

0.009

1.01 (1.01–1.02)

0.0002

1.00 (1.00–1.01)

0.2195

 Neoplasms

1.03 (1.01–1.04)

0.0016

1.01 (0.99–1.03)

0.3548

0.98 (0.97–1.00)

0.0448

 Blood/immune

1.08 (1.05–1.12)

<0.0001

1.05 (1.01–1.09)

0.0096

0.97 (0.94–1.01)

0.1539

 Nervous system

1.01 (1.00–1.03)

0.1198

1.04 (1.02–1.06)

0.0001

1.02 (1.00–1.04)

0.0204

 Eye

1.04 (1.02–1.06)

0.0003

1.04 (1.02–1.06)

0.0002

1.00 (0.98–1.03)

0.7186

 All-cause

1.01 (1.00–1.01)

0.1178

1.01 (1.00–1.02)

0.0147

1.00 (1.00–1.01)

0.3655

 Neoplasms

1.03 (1.00–1.05)

0.0167

1.00 (0.98–1.03)

0.7800

0.98 (0.95–1.00)

0.0521

 Blood/immune

1.08 (1.04–1.12)

0.0001

1.05 (1.01–1.09)

0.0253

0.98 (0.93–1.02)

0.2701

 Nervous system

1.01 (0.99–1.02)

0.5376

1.03 (1.01–1.05)

0.0015

1.02 (1.01–1.04)

0.013

 Eye

1.04 (1.03–1.05)

<0.0001

1.04 (1.02–1.06)

<0.0001

1.00 (0.98–1.02)

0.8665

 All-cause

1.02 (1.00–1.04)

0.1236

1.01 (0.99–1.04)

0.4044

0.99 (0.97–1.02)

0.6295

 Neoplasms

1.01 (0.96–1.07)

0.6159

1.09 (1.02–1.16)

0.0091

1.07 (1.00–1.15)

0.0516

 Blood/immune

1.08 (0.97–1.20)

0.1523

1.14 (1.02–1.27)

0.0025

1.05 (0.92–1.20)

0.4545

 Nervous system

1.03 (0.99–1.08)

0.1715

0.99 (0.95–1.04)

0.7208

0.96 (0.91–1.01)

0.1531

 Eye

1.03 (0.98–1.08)

0.2649

1.01 (0.95–1.06)

0.8028

0.98 (0.92–1.04)

0.4918