One consequence of this was that, categorisation of variables such as RR, enabled an average of 38% of values not to be excluded.
It is also of interest to study survival differences in narrow prognostic categories, to ascertain whether the difference can be better explained by more minute categorisation of factors such as tumour size, and whether the survival advantage of screen-detected tumours is more marked in higher risk or lower risk tumours.
As a result of the categorisation of variables such as age, socio-economic status, questionnaire response and proportion of 50+ in a household, there were very few people in some groups, that is a small increase in absolute numbers resulted in higher percentages.
And although certain events in the play chime with some of Freud's categorisations of dreams, such as the scene in which the dreamer revisits his mother 10 years after her death, there are no direct dream parallels.
There is often a lack of replication for individual risk factors across studies (in some cases attributable to heterogeneity in the categorisation of continuous variables such as birth weight and gestational age).
Early on, his art bridged the apparent gap between abstraction and pop art, the sophistication of his paintings revealing the inadequacy of such categorisations.
As Hacking (2004) notes, classifications affect people, not so much because of people's knowledge of such categorisations, but because of the way in which classifications guide the purpose and actions of relevant institutions.
The dichotomous simplicity of such a categorisation is immediately appealing but fails to reflect adequately the spectrum of risk that exists for all pregnant patients and does not acknowledge the limited clinical utility of current strategies for the prediction of obstetric risk, especially among nulliparae.
Such categorisation of the data (calculation of the period variable and time span) was based on the same assumptions as those discussed in previous studies [ 12, 25- 27].
