Social ecology of intelligence and suicide in the United States

Two proxy variables for regional intelligence, state-level mean scores of 1994-2004 on the American College Test and of 1982, 1993, 1994, and 1998-2004 on the Scholastic Assessment Test, were consistently positively correlated with the averaged regional U.S. suicide rates of 1990-1994. The effects observed in these ecological (group-level) analyses were of small size, with correlation coefficients ranging from .05 to .25, thus mostly falling below the nominal statistical significance level. The present evidence nevertheless adds to several recent findings from international geographical studies by Lester and by Voracek of a positive association of intelligence and suicide mortality by indicating that this pattern may also exist on the within-nation level.     

State IQ and suicide rates in the United States

Previous findings pertaining to the direction (positive or negative) of the ecological correlation between intelligence and suicide rates in the USA have been conflicting. Using novel state IQ estimates, derived from the Scholastic Assessment Test, the American College Test, these tests combined, or the National Assessment of Educational Progress state scores, these estimates were not consistently associated to state suicide rates. Whereas ACT-derived state IQ was significantly positively correlated with suicide rates, the correlation with composite ACT-SAT-derived state IQ was significantly negative and with both SAT-derived and NAEP-derived state IQ also negative but not significant. Validity checks pointed to possible methodological problems with the state IQ estimates. Currently available estimates of state IQ, therefore, seem not appropriate to resolve the question of the direction of the ecological correlation of intelligence and suicide mortality across the USA.     

Regional intelligence and suicide rate: new data for Australia and a synthesis of research

Previous research has shown for the most part positive correlations between intelligence and suicide prevalence on the national level. However, this study found proxies for regional intelligence in Australia (international average domain scores from the PISA 2000 study) to be significantly negatively correlated with the total, male, and female suicide rates of the different administrative divisions of Australia, and this finding was independent of regional wealth. A research synthesis of the current results and those from similar studies of other countries (positive correlations for Austria, Belarus, The British Isles, Denmark, and The Netherlands; inconclusive findings for France, Germany, and the USA) was conducted. This synthesis of research findings showed that positive ecological correlations of intelligence with suicide rate were more likely observed for nations with higher suicide rates and poorer general living conditions, whereas there was no relation with national IQ.     

Educational attainment, intelligence, interstate migration, and suicide rates in the United States: rejoinder to Abel and Kruger (2005)

Abel and Kruger (2005) reported a negative association of educational attainment and suicide rate across the United States. Given strong links between intelligence and educational attainment, this appears to be inconsistent with positive associations of intelligence and suicide rate reported in several other geographical studies. However, the apparent inconsistencies may reflect interstate migration within the U.S. adult population. Testing this hypothesis showed that interstate migration was more strongly related to state suicide rates than educational attainment. Thus, the different results obtained by Abel and Kruger could reflect migration effects, which for the U.S. might render adult-age indicators of educational attainment inappropriate to reflect regional variation in intelligence by place of birth.     

Does Legalized Gambling Elevate the Risk of Suicide? An Analysis of U.S. Counties and Metropolitan Areas

This study addresses a possible link between suicide and casino gambling. Resident suicide rates are analyzed for (a) a 1990 cross-section of 148 U.S. metropolitan areas and (b) before and after the advent of legalized casinos in five U.S. counties. Data are drawn from government and gaming industry sources. In cross-section, metro area suicide is strongly correlated with region, accidental death and homicide rates, age and race composition, and economic vitality, followed by a modest net positive correlation with casino presence. By contrast, the time series analysis yields no evidence of a gambling effect.     

Ancestry, genes, and suicide: a test of the Finno-Ugrian Suicide Hypothesis in the United States

There is now convergent evidence from classic quantitative genetics (family, twin, and adoption studies) and molecular genetic studies for specific genetic risk factors for suicidal behavior. This emerging research field has recently been supplemented by geographical studies concerned with the Finno-Ugrian Suicide Hypothesis (FUSH), which states that population differences in genetic risk factors may partially account for conspicuous geographical patterns seen in suicide prevalence. In particular, the European high-suicide-rate nations constitute a contiguous, J-shaped belt, spanning from Finland to Austria. This area maps onto the second principal component identified for European gene distribution, most likely reflecting a major migration event of the past (i.e., the ancestral adaptation to cold climates and the Uralic language dispersion) still detectable in modern European populations. The present research tested the hypothesis in the United States. Consistent with the hypothesis, available historical (1913-1924 and 1928-1932) U.S. state suicide rates were uniformly positively associated with available state proportions of reported American ancestries from European high-suicide-rate countries (Hungary, Lithuania, Poland, Russia, Slovakia, and the Ukraine). However, contrary to the hypothesis, available contemporary (1990-1994) suicide rates were uniformly negatively associated with these ancestry proportions. The findings of this first test outside Europe are therefore conflicting. A proposal based on the geographical study approach is offered to further the progress of investigations into the genetics of suicide.     

National differences in intelligence and population rates of suicidal ideation, suicide plans, and attempted suicide

Population rates of suicidal ideation, suicide plans or attempted suicide from three independent multinational epidemiological surveys (the WHO/EURO and WHO SUPRE-MISS studies and a third one) were not significantly associated with national IQ figures. This result conflicts with previous evidence from cross-national studies (by Lester and by Voracek) of a positive ecological correlation between level of national intelligence and rates of completed suicide. Across nations, the indicators for the prevalence of suicidal behavior also lacked close correspondence with suicide rates, which may be due to the higher unreliability of assessing covert suicidal behavior (suicide ideas, thoughts, plans, and, to a lesser extent, also suicide attempts) as compared to suicidal behavior that is indisputably overt (completed suicide). Several alternative explanations for the current nil findings are also discussed.     

Characteristic emotional intelligence and emotional well-being

Both theory and previous research suggest a link between emotional intelligence and emotional well-being. Emotional intelligence includes the ability to understand and regulate emotions; emotional well-being includes positive mood and high self-esteem. Two studies investigated the relationship between emotional intelligence and mood, and between emotional intelligence and self-esteem. The results of these studies indicated that higher emotional intelligence was associated with characteristically positive mood and higher self-esteem. The results of a third study indicated that higher emotional intelligence was associated with a higher positive mood state and greater state self-esteem. The third study also investigated the role of emotional intelligence in mood and self-esteem regulation and found that individuals with higher emotional intelligence showed less of a decrease in positive mood and self-esteem after a negative state induction using the Velten method, and showed more of an increase in positive mood, but not in self-esteem, after a positive state induction. The findings were discussed in the light of previous work on emotional intelligence, and recommendations were made for further study.     

Elevated Suicide Levels Associated with Legalized Gambling

There has been no systematic, large-scale statistical investigation of the link between gambling and suicide, despite the suggestion of such a link from small-scale case studies. This article examines whether gamblers or those associated with them are prone to suicide and whether gaming communities experience atypically high suicide rates. Las Vegas, the premier U.S. gambling setting, displays the highest levels of suicide in the nation, both for residents of Las Vegas and for visitors to that setting. In general, visitors to and residents of major gaming communities experience significantly elevated suicide levels. In Atlantic City, abnormally high suicide levels for visitors and residents appeared only after gambling casinos were opened. The findings do not seem to result merely because gaming settings attract suicidal individuals.     

The Epidemiology of Homicide followed by Suicide: A Systematic and Quantitative Review

This systematic review of population based studies of homicide followed by suicide was conducted to examine the associations between rates of homicide‐suicide, rates of other homicides and rates of suicide. The review analysed 64 samples, including the case of an outlier (Greenland) that were reported in 49 studies. There was a significant association between the rates of homicide‐suicide and those of other homicides in studies from the U.S.A. Outside the U.S.A. there was no clear association between homicide‐suicide and other homicide but there was modest but significant association between rates of suicide and homicide‐suicide. Homicide‐suicide appears to be closer in epidemiological terms to homicide than suicide in regions with high rates of homicide and measures to reduce homicide in these regions may also reduce homicide‐suicide.     

The Relationship between General Population Suicide Rates and the Internet: A Cross‐National Study

Internet Web sites and chat rooms have been reported both to promote suicides and have a positive beneficial effect on suicidal individuals. There is a paucity of studies examining the role of the Internet in general population suicide rates. The relationship between general population suicide rates and the prevalence of Internet users was examined in a cross‐national study using data from the World Health Organization and the United Nations Web sites. The prevalence of Internet users was significantly and positively correlated with general population suicide rates in both sexes. On multiple regression analysis the prevalence of Internet users was independently associated with general population suicide rates in males, and this independent relationship in females approached statistical significance. Caution should be exercised in the attribution of a causal relationship and the direction of this relationship because of the cross‐sectional and ecological study design whereby the findings are subject to ecological fallacy. However, the findings identify and support a need for further research.     

Cross-national social ecology of intelligence and suicide prevalence: integration, refinement, and update of studies

This study integrates, refines, and updates previous findings pertaining to positive ecologic (population-level) associations between intelligence and suicide prevalence across nations by using corrected and revised national IQ estimates and, further, a quality-of-human-conditions index, both recently published by Lynn and Vanhanen. Across a global 85-nation sample of sex-specific total suicide rates and a Eurasian 48-nation sample of sex-specific elderly suicide rates, these were positively associated with updated national IQ estimates. The associations were stronger for the general population than for elderly persons, independent of the quality of human conditions, and notedly stronger in exponential fitting of suicide rates with national IQ than in linear fitting, thereby indicating that shifts or differences in national IQ correspond to proportional, not absolute, changes in suicide rates. Implications of these findings and the question of generalizability of such associations to the individual level are discussed.     

State IQ and elderly suicide rates in the United States

Paralleling previous findings with state suicide rates of the total population, the associations of state suicide rates of elderly persons with regional IQ estimates across the USA were inconsistent (positive, negative, or nil), depending on the source of available state IQ estimates used in the analysis. The implications of these findings and directions for further inquiry are discussed.     

Suicide coverage in U.S. newspapers following the publication of the media guidelines

A nationally representative sample of 968 local and national newspapers was examined to determine whether the 2001 U.S. media guidelines were followed in articles published in 2002-2003, and featuring individual cases of suicidal behavior (N = 157). We found that, during this period of time, U.S. newspaper suicide coverage did not consistently reflect the influence of the media guidelines. On the positive side, only 19% of stories included inappropriate imagery. On the negative side, suicide stories often detailed suicide method (56% of stories) and location (58%), and rarely provided information about warning signs and risk factors (1%), the roles of depression (4%) and alcohol (2%), and prevention resources (6%). Our findings, together with previous evidence, suggest the need for sustained dialogue with the media about suicide reporting.     

Regional intelligence and suicide rate in Germany

Regional intelligence proxies (intranational average domain scores from the PISA 2000 and 2003 studies) were not reliably associated with the suicide rate across the states of Germany, thereby not replicating findings of a positive ecological correlation of regional intelligence and suicide prevalence from other within-nation studies (Austria, Belarus, the British Isles, Denmark, The Netherlands, and the USA).     

An ecological study of community-level correlates of suicide mortality rates in the Flemish region of Belgium, 1996-2005

An ecological study of age-standardized suicide rates in Belgian communities (1996-2005) was conducted using spatial regression techniques. Community characteristics were significantly related to suicide rates. There was mixed support for the social integration perspective: single person households were associated with higher suicide rates, while religious participation was unrelated and both immigration and the presence of non-European inhabitants had a negative impact. Deprivation had a positive relation with suicide. Population density had a negative influence on suicide rates. Areas with older populations had higher suicide risks than expected. A spatial contagion effect of neighboring communities was present for men. In the conclusion, hypotheses are presented on why an aging population could be associated with higher suicide rates in the community.     

Sweden: income and suicide

Previous publications have reported two conflicting patterns describing the relationship between income and suicide in Sweden; positive and negative. Methodologically the studies have differed, and the analysis has been limited to a few areas. To better understand the relationship, a nationwide, cross-sectional, ecological study of the 290 municipalities in Sweden was planned. OLS regression analyses showed the overall and female suicide rates were negatively related to income, while the effect on male suicide rates was not statistically significant. The results confirm earlier findings of a negative relationship between income and suicide.     

Exponential fitting of suicide rate and national intelligence estimates

Positive ecological (group-level) associations of Lynn and Vanhanen's 2002 national intelligence (IQ) estimates with the suicide rates of men and women across 85 countries and with the suicide rates of the male, female, and total elderly population across 48 Eurasian countries reported recently is extended by the finding that this ecological association was notedly better accounted for by exponential fitting than by linear fitting. This evidence implies that the effect of a shift in the national IQ on the suicide rate is proportional, not absolute. As a rule of thumb, a 5-point shift in national IQ roughly corresponds to a 50% change in the national suicide rate.     

Suicide mortality among Kentucky farmers, 1979-1985

Farmers may be at high risk for suicide because of their social environment and because of chemical exposure resulting in neurotoxic effects in the workplace. Age-specific suicide rates are compared for Kentucky white farmers, Kentucky white males, and U.S. white males. Data for suicides occurring in Kentucky represent the 7-year period between 1979 and 1985; data for the United States suicides represent the period 1980. Overall, suicide rates were highest for Kentucky farmers, followed by Kentucky males and then by U.S. males. All males were most likely to use firearms as the mode of suicide, but the farmers used firearms significantly more often than the U.S. males, as did the other Kentucky males. These findings and other evidence support the need to assess suicide rates in this occupational group in other states, to begin suicide prevention programs for Kentucky, and to work to identify risk factors contributing to the Kentucky farm suicides.