What does reference date mean?

[tombeteende]

What happened?

There is no documentation about what reference date means, I couldn't trace it in the code or to see how it influences the data I generate (I tried with several reference dates)
(my ultimate goal is to create data that ends in the future and not today)

Environment

- OS: MacOs
- Java:

Relevant log output

No response

[dehall]

Yes I see this can be documented better. The reference date is used to calculate birthdates, such that the ages of the generated population match the age distribution within the target demographics. By default the reference date matches the end date of the simulation which is the current day.

Eg, let's say the age breakdown for a given region is:
0 – 14 years: 18.2%
15 – 24 years: 13.0%
25 – 54 years: 39.0%
55 – 64 years: 12.9%
65 years and over: 16.8%

When Synthea runs it tries to meet those %s by picking a target age for each record, then their birthdate is reference_date - target_age

[jawalonoski]

(my ultimate goal is to create data that ends in the future and not today)

Also, if you want to end in the future, you should be looking at [-e endDate as YYYYMMDD]

[tombeteende]

Thanks. If you can refer me to the documentation you mentioned it would be great. I can only see the flags (i.e. -e endDate as YYYYMMDD ) without more details and some of the flags are not trivial.

[jawalonoski]

Thanks. If you can refer me to the documentation you mentioned it would be great. I can only see the flags (i.e. -e endDate as YYYYMMDD ) without more details and some of the flags are not trivial.

The documentation in this area is not complete. For the -e flag specifically, refer to this article: https://github.com/synthetichealth/synthea/wiki/Recreating-a-Dataset

In general, our documentation is our GitHub Wiki: https://github.com/synthetichealth/synthea/wiki