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rcpch / rcpchgrowth-python

A python package to produce calculations for all growth issues
GNU Affero General Public License v3.0
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midparental height discrepancy #43

Closed eatyourpeas closed 3 weeks ago

eatyourpeas commented 3 weeks ago

For the following parental heights: father: 167cm, mother 151cm, midparental centile should be between 9-25th centiles but is plotting lower

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eatyourpeas commented 3 weeks ago

Update from prof. wright: The lookup (the nonagram on the paper charts) is based on the regression of both parental z scores on child’s height so to replicate this you have to convert each parents’ height to z scores, take the mean and multiply it by the regression coefficient which is 0.5 (or near as dammit) to give parental height prediction So in summary, simplified, to (MatHtz +PatHtz)/4 Then subtract this from the child’s Z score if you want a measure in Z score units of how discrepant the child is.

eatyourpeas commented 3 weeks ago

Wright-1999-The strengths and limitations of p.pdf