Page 77 - Sample Moderate prematurity, socioeconomic status, and neurodevelopment in early childhood

of statistical interaction in logistic models implies that having both risk factors increases the risk of neurodevelopmental problems considerably, relative to having only one of the risk factors. In other words, a multiplicative risk model applies.
The Swedish conscript study
The Swedish conscript study is a register-based study using data of over 45,000 men who were conscripted for military service in 1969 and 1970, and it covers a follow-up period of nearly 40 years. For this reason the study is well-suited to assess effects of mental and physical well-being on health during the course of the conscripts’ lives. Therefore, the possibility of reverse causation is limited, enabling the researcher to disentangle cause and effect. On the other hand, long time spans between exposure and outcomes may either underestimate or overestimate the real effects. Emotion regulation was measured at conscription in 1969 and 1970 and follow-up for CHD occurred until 2009. The effect of emotion regulation might have been diluted over the long follow-up period, but it is unknown to which degree emotion regulation relates to healthy ageing.66 Furthermore, lifestyle- associated factors, i.e. BMI, cardiorespiratory fitness, smoking, and blood pressure, were likely to change during follow-up. However, changes in these risk factors later on were consequences rather than causes of emotion regulation capacity, which may have led to an underestimation of the real effects.57, 58
As mentioned above, the assessment of the conscripts’ mental functioning
took place at conscription, which limited us in interpreting what the psychologists
had exactly measured in relation to current theory on emotion regulation. The
available information on the assessment of emotion regulation fits with core
features of emotion regulation, although the described concept may also fit
related constructs, such as coping and mood regulation. As yet it is unknown
how the constructs of emotion regulation, coping ability, and mood regulation
are interrelated.66 The interrater reliability of the interviewing psychologists was
tested a few years after conscription, on the basis of 30 tape-recorded interviews 7 scored by 30 psychologists, and was rated as ‘very high’ (r=0.86) for the overall
assessment of mental functioning.85, 86
Lastly, the generalizability of study outcomes is limited, in the sense that only men participated in the study. As a consequence, our findings cannot be generalized to women. Furthermore, the findings do not necessarily apply to CHD events at older ages because participants were about 60 years of age at the end of follow-up. Besides the fact that participants consisted of Swedish men only, the probability
General discussion
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