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NEWS.md

@@ -18,6 +18,7 @@
 * Reduced the number of long-running examples. By @sbfnk in #459 and reviewed by @seabbs.
 * Changed all instances of arguments that refer to the maximum of a distribution to reflect the maximum. Previously this did, in some instance, refer to the length of the PMF. By @sbfnk in #468.
 * Fixed a bug in the bounds of delays when setting initial conditions. By @sbfnk in #474.
+* Added input checking to `estimate_infections()`, `estimate_secondary()`, `estimate_truncation()`, `simulate_infections()`, and `epinow()`. `check_reports_valid()` has been added to validate the reports dataset passed to these functions. Tests are added to check `check_reports_valid()`. As part of input validation, the various `*_opts()` functions now return subclasses of the same name as the functions and are tested against passed arguments to ensure the right `*_opts()` is passed to the right argument. For example, the `obs` argument in `estimate_secondary()` is expected to only receive arguments passed through `obs_opts()` and will error otherwise. By @jamesmbaazam in #476 and reviewed by @sbfnk and @seabbs.
 
 ## Model changes