Psychometric tests differences between studies

The procedure of psychometric testing varies between the different studies included in this chapter. While many conducted no psychometric tests at all, two studies conducted a confirmatoiy factor analysis (CFA), two performed an exploratory factor analysis (EFA), and 10 studies did both. Despite this difficulty, we found only one study (Piyseley 2008) out of 10 which performed a CFA in order to test the original factor stracture of the HSPSC questionnaire, with several unacceptable thresholds for both absolute and incremental fit indices. With regards to the EFAs, the dimensions Staffing , Communication openness , Organisational learning and Teamwork across hospital units , appeared to be less stable. 

In a placebo-controlled, crossover study in 12 healthy men, lithium and mirtazapine had no effect on the pharmacokinetics of each other and there was no difference in psychometric testing between the addition of lithium and placebo (8). 

In some studies using blood lead as a measure of body burden there was a long period of time between when the blood was obtained, and when the psychometric tests were carried out. Since blood is a measure of body burden which reflects predominantly current exposure to lead, this can be relevant if exposure changes in some way. In some studies it was shown that in a number of children there was a considerable difference in their... 

Psychometric data from this study (Schroeder and Hawk, 1987) have been reviewed above. Sensory conditioning was limited to the passive test due to the age range of the children. Contrary to earlier findings (Otto ei al, 1981, 1982), slow wave voltage did not vary with PbB levels. Differences between the two groups studied, however, may have contributed to the discordant results. Children in the earlier studies were somewhat younger (1 to 6 versus 3 to 7 years) and were exposed by different routes (secondary occupational exposure versus lead paint and contaminated soil) than children in the replication study (see review by Otto, 1985). More recent analyses of these slow wave data and their implications, as well as other results, are discussed by Otto elsewhere in this volume. 

The present study was designed to evaluate the relationship between different biological indicators of body lead burden and some neuropsychological functions in 7-8-year-old children, living in an industrial area polluted by lead. The neuropsychological functions were estimated by a battery of 6 psychometric tests. Lead was measured in blood, hair and teeth, and mean levels of 11.45 jug dl 9.94 figg and 6.80 jUg g respectively, were obtained. 

In our study, the children recruited had been exposed to unstable conditions of lead exposure, with high levels at birth, decreasing after the first years of life. Four biochemical indicators were analysed three exposure parameters (lead in blood, hair, and teeth) and one parameter of effect (ALA-D activity). The possible relationship between current and long-term indicators was evaluated in our exposure conditions. Numerous standardized psychometric tests, selected for their sensitivity and ability to assess different cognitive functions, were carried out. 

Through the initial web-based literature search on Medline and Web of Science, performed in March 2012, we identified 26 publications on the use of the HSPSC in a European country, which were published between January 2003 (when the HSPSC had originally been developed) and February 2012. We reviewed these publications focusing on instrument development (i.e. the translation and/or adaptation process), data collection process (e.g. in a pilot or field study) and psychometric evaluation (i.e. tests performed and key results of these tests) in different coimtries. 

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