Table 2.
Model estimates of predictors of HIV-positive status according to GEE analysis
|
Independent variables |
Complete dataset |
Imputed dataset |
||||
|---|---|---|---|---|---|---|
| Estimate | SE | P value | Estimate | SE | P value | |
| Intercept |
-0.593 |
0.050 |
<0.001 |
-0.631 |
0.048 |
<0.001 |
| Calendar year |
-0.277 |
0.038 |
<0.001 |
-0.254 |
0.036 |
<0.001 |
| Year of birth |
-0.039 |
0.009 |
<0.001 |
-0.043 |
0.009 |
<0.001 |
| Year of birtha |
-0.054 |
0.012 |
<0.001 |
-0.042 |
0.010 |
<0.001 |
| Year of birthb |
0.019 |
0.005 |
<0.001 |
0.013 |
0.005 |
0.012 |
| Age |
0.043 |
0.009 |
<0.001 |
0.035 |
0.008 |
<0.001 |
| Agec |
-0.048 |
0.006 |
<0.001 |
-0.043 |
0.006 |
<0.001 |
| Aged |
0.012 |
0.002 |
<0.001 |
0.011 |
0.002 |
<0.001 |
| Female, non-Swiss, non-injector |
-1.760 |
0.492 |
<0.001 |
-1.435 |
0.543 |
0.011 |
| Female, non-Swiss, ever injector |
0.497 |
0.158 |
0.002 |
0.457 |
0.150 |
0.002 |
| Female, Swiss, non-injector |
-1.344 |
0.197 |
<0.001 |
-1.372 |
0.201 |
<0.001 |
| Female, Swiss, ever injector |
0.186 |
0.069 |
0.007 |
0.167 |
0.065 |
0.011 |
| Male, non-Swiss, non-injector |
-1.520 |
0.299 |
<0.001 |
-1.422 |
0.261 |
<0.001 |
| Male, non-Swiss, ever injector |
-0.074 |
0.109 |
0.496 |
-0.087 |
0.107 |
0.417 |
| Male, Swiss, non-injector | -1.547 | 0.149 | <0.001 | -1.567 | 0.143 | <0.001 |
The time variables were rescaled to fit the GEE model as follows: calendar year = logarithm of year - 1990, year of birth = year - 1960, age = age - 30. aYear of birth = Year of birth × Year of birth / 10. bYear of birth = Year of birth × Year of birth × Year of birth / 100. cAge = Age × Age / 10, dAge = Age × Age × Age / 100. The group ‘Male, Swiss, ever injector’ was reference category and is therefore omitted from the independent variable list. SE, standard error.