Statistical analysis
All the data was coded anonymously. The Shapiro-Wilk test confirmed that
all data were normally distributed. Missing value analysis confirmed
that missing data was randomly distributed and excluded for the
comparisons. Descriptive statistics for each group were analysed and
reported in the results with their mean (SD); independent sample t-test
was used to compare the group means. Pearson’s correlation analysis were
used to compute the correlation between the two methods in each group,
and Bland-Altman plot analysis used to estimate the agreement within the
axSpA cohort. Correlation coefficients 1.00 to 0.90 were interpreted as
very strong, 0.89 to 0.70 as strong, 0.69 to 0.50 as moderate, 0.49 to
0.30 as weak, and 0.29 to 0 as very weak. Frequencies and percentages
were used to summarise the feasibility data. P values <0.05
were considered statistically significant, and all tests were 2-tailed.
Statistical analyses were performed using SPSS version 28 (IBM SPSS
Statistics).