A time-varying measurement error model for age of onset of a psychiatric diagnosis: applied to first depressive episode diagnosed by the Composite International Diagnostic Interview (CIDI)

A substantial degree of uncertainty exists surrounding the reconstruction of events based on memory recall. This form of measurement error affects the performance of structured interviews such as the Composite International Diagnostic Interview (CIDI), an important tool to assess mental health in the community. Measurement error probably explains the discrepancy in estimates between longitudinal studies with repeated assessments (the gold-standard), yielding approximately constant rates of depression, versus cross-sectional studies which often find increasing rates closer in time to the interview. Repeated assessments of current status (or recent history) are more reliable than reconstruction of a person's psychiatric history based on a single interview. In this paper, we demonstrate a method of estimating a time-varying measurement error distribution in the age of onset of an initial depressive episode, as diagnosed by the CIDI, based on an assumption regarding age-specific incidence rates. High-dimensional non-parametric estimation is achieved by the EM-algorithm with smoothing. The method is applied to data from a Norwegian mental health survey in 2000. The measurement error distribution changes dramatically from 1980 to 2000, with increasing variance and greater bias further away in time from the interview. Some influence of the measurement error on already published results is found.     

Extreme probabilities for contingency tables under row and column independence with application to fisher's exact test

Theorerms are proved for the maxima and minima of IIR_i!/IIC_j!/T!II_yij ! over r× c contingcncy tables Y=(y_ij) with row sums R₁,…,R_r, column sums C₁,…,C_c, and grand total T. These results are imlplemented into the network algorithm of Mehta and Patel (1983) for computing the P-value of Fisher's exact test for unordered r×c contingency tables. The decrease in the amount of computing time can be substantial when the column sums are very different.     

Exposure to Community Violence,Suicidality, and Psychological Distress Among African American and Latino Youths: Findings From the CDC Youth Violence Survey

The present investigation explored risk and protective factors for suicidal ideation and behavior in a sub-sample of African American and Latino adolescents (n = 2,626) who participated in the 2004 Centers for Disease Control Youth Violence Survey. Structural equation modeling was used to explore exposure to violence at the community level as a contextual factor that could potentially influence depressive symptomatology, substance abuse, parental support, social support, and suicidality among study participants. Findings indicated that exposure to violence at the community level was not directly related to suicidality among this population of urban adolescents. However, it was directly related with several other variables under study in the model, which in turn were directly related with suicidality. Tests of invariance revealed several across-group differences, particularly by race and gender, in how the identified risk and protective factors in the model related to suicidality. Implications for research and practice with urban, ethnic minority, adolescent populations are discussed.     

Protecting children in Scotland: examining the impact of the Children (Scotland) Act 1995

This paper discusses findings from a small‐scale study of the impact on child protection practice following implementation of the Children (Scotland) Act 1995. The Act introduced three new measures to allow the state to intervene in families to protect a child where there is a risk of significant harm. These include the child protection order, the child assessment order and the exclusion order. The child protection order provides for the removal of a child to (or his or her retention in) a place of safety. In the first two years of the operation of the 1995 Act fewer applications were made for this order compared with similar provisions under the previous legislation. This reduction in applications appears to be related to unfamiliarity with new legislation; greater scrutiny resulting from the more formal application to the sheriff court; and the introduction of a new legal criterion for intervention, the presence or likelihood of ‘significant harm’. The introduction of the ‘no order’ principle into Scottish child care law is also likely to be a factor.     

Empirical assessment of present value relations

This paper summarizes the literature on estimation and testing of present value relations. Twenty-four test statistics are illustrated and compared in a simulation experiment utilizing six different data generation models. The test statistics are calculated for actual Standard and Poor's 500 annual stock price and dividend data, and the results are interpreted in light of the Monte Carlo experiments.