Table 5 Key variables included in the regression analysis for prediction of a decrease in plasma FT3I after initiation of levothyroxine therapy

Gender (male/female)

-0.033

0.850

Age at diagnosis (years)

-0.215

0.179

Weight at HQRL assessment (kg)

-0.033

0.850

LT4 intake (morning/at bedtime)

0.010

0.952

Smoking

-0.021

0.883

Time to euthyroidism (days)

0.114

0.456

LogAntiTPO at diagnosis

0.025

0.861

FT4I at diagnosis

-0.196

0.819

FT3I at diagnosis

0.430

0.441

FT4i/logTSH at diagnosis

0.249

0.590

FT4I/FT3I ratio at diagnosis

0.281

0.658

LogTSH at diagnosis

0.036

0.921

Brand of LT4 (Eltroxin® or Euthyrox®)

-0.087

0.566

Time from diagnosis to HRQL assessment (days)

-0.027

0.841

Composite score

0.851

0.542

Goitre score

-0.148

0.377

Hypo score

-0.095

0.604

Tiredness score

-0.478

0.168

Cognition score

-0.256

0.488

Anxiety score

0.105

0.773

Depression score

0.044

0.870

Emotional susceptibility score

-0.192

0.547

Social score

-0.177

0.667

Daylife score

0.161

0.521

Overall Quality of Life score

-0.056

0.708

By backward stepwise regression

 FT3I at diagnosis

0.446

< 0.001

 Anxiety

0.264

0.015