Luckily DD was 5 this year, not 4, so I didn't have to do it. These would have been my valid reasons to object:
1. I don't have time.
2. I don't have time.
3. I don't want DD in a doctors waiting room around sick people for no good reason
4. There was (and is) absolutely nothing wrong with DD and as her mother if I had any concerns I would take her to the doctor at my discretion, and request the tests I wanted
5. I have had nothing but bad experiences at health check ups with DD, causing unnecessary anxiety and concerns that in hindsight were absolutely unfounded. Just go and read some of the threads on here from brilliant mums who have left chn check ups in tears having been made to feel like there is something wrong with their child and/or their parenting. Completely unnecessary if you ask me.