Quality of suicide mortality data
There are several important caveats that need to be considered when evaluating suicide mortality data. Of the WHO 172 Member States for which estimates were made for the year 2012, only 60 have good-quality vital registration data that can be used directly to estimate suicide rates.
The estimated suicide rates in the other 112 Member States (which account for about 71% of global suicides) are necessarily based on modelling methods. As might be expected, good quality vital registration systems are much more likely to be available in high-income countries. The 39 high-income countries with good vital registration data account for 95% of all estimated suicides in high-income countries, but the 21 LMICs with good vital registration data account for only 8% of all estimated suicides in LMICs.
This problem of poor-quality mortality data is not unique to suicide, but given the sensitivity of suicide – and the illegality of suicidal behaviour in some countries – it is likely that under-reporting and misclassification are greater problems for suicide than for most other causes of death. Suicide registration is a complicated, multilevel procedure that includes medical and legal concerns and involves several responsible authorities that can vary from country to country.
Suicides are most commonly found misclassified according to the codes of the 10th edition of the International Classification of Diseases and Related Health Conditions (ICD-10) as “deaths of undetermined intent” (ICD-10 codes Y10-Y34), and also as “accidents” (codes V01-X59), “homicides” (codes X85-Y09) and “unknown cause” (codes R95-R99).