Many federal workers are seeing that using their sick leave time rather than having them added into their annuity calculations would be more beneficial with receiving the pay rate that they are receiving at this time for every hour that they use. This would technically be more than what they would get from their annuity payments if their sick leave hours were formulated into the benefits.
In the Code of Federal Regulation in 5 CFR 630, federal workers can only use their sick leave for reasons that are permitted such as appointments or treatments regarding dental, medical, or optical reasons, needing to care for a family member that is unable to take care of themself, if you are adopting a child and are unable to go to work due to handling matters pertaining this adoption, or if you are incapable of working your job for health reasons.
Those that are or will need to be gone for over three days will need to provide proof of the medical reason, whether for yourself or your family member.
Those that take sick leave for any other non-permitted reasons, they may face some kind of disciplinary action along with a record of the abuse in their file. This applies to those that are about to retire as well, which can affect you, possibly losing reliable references that you may need later on in life.