Adjusting Suicide Rates in a Military Population: Methods to Determine the Appropriate Standard Population

The choice of the standard population is important when calculating adjusted rates for a military population: results can influence policies and funding allocations for programs and initiatives for suicide prevention. We describe the methodological considerations and decision-making process used in choosing a standard population for adjusting rates to compare suicide among US Army soldiers and the general US population. We examined 5 different standard populations, using the direct method to adjust annual suicide rates for the Army and the US population, 2004 to 2015, for age and for age and sex. The pattern of the Army and US population age- and sex-adjusted rates remained consistent with crude rates when adjusted to any of the Army standard population distributions. Using an Army distribution as the standard population produces suicide rates consistent with routine messaging about suicide trends among Army soldiers.