Mid parental height 123 causes chart error

[ryanlewis94]

entering 123 for both maternal and paternal height causes an error when displaying the chart

[eatyourpeas]

Thanks for picking this up @ryanlewis94 - I can look into better error handling for the midparental heights within the charts themselves, and our client. Just to be aware though that 123 cm is impossibly small for two parents and this sort of error should be trapped further back in any work flow outside of the charts.

[raspberrycodes]

@eatyourpeas Hi Simon, I am looking into this to see if there is validation that we need to do on our end and I can see that we have set input validation on the maternal and paternal fields to between 50-245.

The minimum value of 50 was set based on the arbitrary value from this file (line 44): https://github.com/rcpch/rcpchgrowth-python/blob/live/rcpchgrowth/constants/validation_constants.py

I did some more testing and found that the maximum height that I could enter where the value is the same for maternal and paternal is 130cm each. If I enter them both as 131cm or higher (up to the maximum of 245 each) then the mid-parental height returns and plots fine. But 130 each or lower gives us the error that Ryan posted above.

Also just to add, the testing that I did was on a patient who had 40 weeks gestation and I didn't change this at all, so I am curious about the 'uk90_preterm' message. Is this a red herring?

Thank you!

[eatyourpeas]

Sorry this is a red herring. It happens because there is no validation for parental heights in the server, which there should be. The actual error here reported does need looking at but that is not the cause. Thank you very much for picking this up.

We recently overhauled midparental height calculations but forgot to apply any validation to the parameters.

Validation for all measurements was only recently agreed because although the intention was to have SD-based validation, well that is complicated - see discussion here for the detail. This is now implemented but this endpoint was forgotten - so that is my bad.

I will imminently release a fix in the server and that should fix this, but we will need a fall back so I will leave this open til I have done that.

For reference,±8 SDS cut offs are:

reference	sex	minimum height (cm)	maximum height (cm)
uk-who	male	121.60	233.08
uk-who	female	115.33	211.95
cdc	male	117.91	232.61
cdc	female	110.52	214.34

ADDENDUM
Note this comment has been updated - SDS cut offs are ±8, not 6. I have updated the table above