class: replacement therapy, underreplacement, overreplacement, negative age: continuous sex: M, F on thyroxine: f, t query on thyroxine: f, t on antithyroid medication: f, t sick: f, t pregnant: f, t thyroid surgery: f, t I131 treatment: f, t query hypothyroid: f, t query hyperthyroid: f, t lithium: f, t goitre: f, t tumor: f, t hypopituitary: f, t psych: f, t TSH measured: f, t TSH: continuous T3 measured: f, t T3: continuous TT4 measured: f, t TT4: continuous T4U measured: f, t T4U: continuous FTI measured: f, t FTI: continuous TBG measured: f, t TBG: continuous referral source: WEST, STMW, SVHC, SVI, SVHD, other