Deductive closure

This is a brief review of issues over which Henry Kyburg and I differed concerning the requirement that full beliefs should be closed under deductive consequence.     

The Gender Paradox in Suicide

In most Western countries females have higher rates of suicidal ideation and behavior than males, yet mortality from suicide is typically lower for females than for males. This article explores the gender paradox of suicidal behavior, examines its validity, and critically examines some of the explanations, concluding that the gender paradox of suicidal behavior is a real phenomenon and not a mere artifact of data collection. At the same time, the gender paradox in suicide is a more culture-bound phenomenon than has been traditionally assumed; cultural expectations about gender and suicidal behavior strongly determine its existence. Evidence from the United States and Canada suggests that the gender gap may be more prominent in communities where different suicidal behaviors are expected of females and males. These divergent expectations may affect the scenarios chosen by females and males, once suicide becomes a possibility, as well as the interpretations of those who are charged with determining whether a particular behavior is suicidal (e.g., coroners). The realization that cultural influences play an important role in the gender paradox of suicidal behaviors holds important implications for research and for public policy.     

Psychosocial and pharmacological treatment of patients following deliberate self-harm: the methodological issues involved in evaluating effectiveness.

Development of effective treatments for patients following deliberate self-harm (self-poisoning or self-injury) is a very important element in suicide prevention. The randomized controlled trial (RCT) is the mainstay of evaluation of treatments. In a systematic review of the literature, the effectiveness of treatments based on RCTs was examined and the quality of the RCTs was assessed. Twenty trials were identified, and where possible, these were grouped on the basis of similarities among the types of treatment. In this paper, we examine the methodological aspects of the trials and consider what may be learned that will assist in the design of future studies in this field. The methodological quality of the trials was reasonable, but most trials included too few participants to detect clinically important differences in rates of repeated self-harm. In planning future trials, the following major issues should be addressed: investigators should perform power calculations to determine the number of subjects necessary to detect clinically important effects, provide information on method of randomization and interventions, use standard measures of outcome, and focus on homogeneous subgroups of patients. Improving the methodology of future studies in this field will be essential if sound evidence is to be obtained which can inform effective service provision for deliberate self-harm patients.