Statistical models of Danish drinking water composition and sialolithiasis from 2000 to 2010
| Estimate | SD | T-Value | p Value | |
|---|---|---|---|---|
| Calcium model | ||||
| Copenhagen region (east Zealand) | 12.71 | 5.07 | −1.40 | 0.165 |
| Western Zealand region | 16.09 | 4.84 | 3.32 | 0.001 |
| North West Denmark region | −5.77 | 5.40 | −1.07 | 0.289 |
| South West Denmark region | 0.11 | 4.12 | 0.03 | 0.979 |
| Mean age | −1.43 | 0.73 | 1.96 | 0.054 |
| Per cent females | 475.77 | 261.49 | 1.82 | 0.072 |
| Drinking water calcium | 0.22 | 0.08 | 2.69 | 0.009 |
| Drinking water pH | 23.12 | 13.63 | 1.70 | 0.094 |
| Adjusted R2 0.50 | ||||
| Magnesium model | ||||
| Copenhagen region (East Zealand) | 11.24 | 5.57 | 2.02 | 0.047 |
| Western Zealand region | 11.96 | 5.89 | 2.03 | 0.045 |
| North West Denmark region | −4.41 | 5.41 | −0.82 | 0.417 |
| South West Denmark region | 1.54 | 4.08 | 0.38 | 0.706 |
| Mean age | −1.63 | 0.76 | −2.14 | 0.035 |
| Per cent females | 492.66 | 263.31 | 1.87 | 0.065 |
| Drinking water magnesium | 1.84 | 0.80 | 2.29 | 0.024 |
| Drinking water pH | 8.76 | 11.63 | 0.75 | 0.454 |
| Adjusted R2 0.49 | ||||
| Hydrogen carbonate model | ||||
| Copenhagen region (East Zealand) | 9.66 | 5.39 | −1.79 | 0.077 |
| Western Zealand region | 9.16 | 5.98 | 1.53 | 0.130 |
| North West Denmark region | −3.93 | 5.28 | −0.74 | 0.459 |
| South West Denmark region | −0.55 | 4.10 | −0.13 | 0.893 |
| Mean age | −1.65 | 0.74 | −2.24 | 0.028 |
| Per cent females | 419.62 | 261.11 | 1.61 | 0.112 |
| Drinking water hydrogen carbonate | 0.09 | 0.03 | 3.06 | 0.003 |
| Drinking water pH | 17.33 | 12.08 | 1.43 | 0.155 |
| Adjusted R2 0.51 | ||||
Estimates, t values, p values and adjusted R2 values for three models relating drinking water calcium, magnesium and hydrogen carbonate levels to the incidence of hospital-admitted sialolithiasis in the years from 2000 to 2010 (ie, number of cases per 100 000 citizens per year) on a municipality level (n=98).