Re: [Gnumed-devel] Medication lists - Duration - Started

[Busser, Jim]

On 2013-07-29, at 12:48 PM, Karsten Hilbert <address@hidden> wrote:

>> Until this issue is within GNUmed resolved, can I
>> 
>> 1) remove the constraint clin_when NOT NULL, and
>> 
>> 2) at my next GNUmed database upgrade,
>> 
>>      replace all missing values for clin_when with January 1, 1900
>>      reapply the constraint
>>      perform the upgrade
>>      remove the constraint
>>      replace all values for clin_when with NULL where clin_when = January 1, 
>> 1900
>> 
>> ? 
> 
> It'll bite you in various places.

*Will* or "you  cannot be sure that it won't" ?

I could see no dependence, at least not within the table structure, on there 
having to be a value in clin_when bearing in mind that the only trigger to 
reference it recognizes a value of NULL.

Are you talking about the client (middleware) being unhappy?

Maybe you are expecting an adverse interaction if a value for Duration exists 
(as currently defined) without a value for clin_when against which to compute.

Of course, when "Started" cannot be known with certainty, duration cannot be 
defined with any more meaning. Which is why I am pleading to the project to 
accept the clinical necessity of recognizing that a patient is taking a 
medication whose start date is not feasible to determine with accuracy, and 
that it is reasonable to reframe (redefine) duration to dually cover:

- the total duration *when* the start date was known, and in any event
- the future date until which it is intended that a drug be taken (which can be 
known even when the start date was not confidently known)

-- Jim