The significance of SES for the HRQOL in the context of cardiac rehabilitation is not surprising, although there has thus far been little proof, as social inequality in cardiovascular diseases has been studied on several occasions and correlations have been found, for example with heart disease mortality [ 51].
For longitudinal studies, the impact of a misspecification of the parameters will not only depend on the value of the variance of the latent variable σ but also on the whole covariance matrix, i.e. on the variance of the latent variable at each measurement occasion and its correlation between measurement occasions.
On almost all occasions, the compensation requested can be fulfilled quantitatively: both signals are highly correlated (correlation equals 0.90) with a slope equal to 1.
Test-retest reliability testing of the scales was performed on the data collected from respondents who completed the questionnaire on two occasions, which showed significant correlation between the two assessment occasions (intra class correlation coefficient was 0.87).
In those patients studied on more than one occasion, there was good correlation between the AUCHD determined on the two courses (r=0.73).
Further, as previously reported, test-retest reliability of the tenderness score in 64 of the present participants, who was re-tested on a later occasion, was good (Intraclass Correlation Coefficient (ICC) = 0.88) [ 22].
There was no pattern of repeated QC failure by a single subject sampled on more than one occasion, neither was there correlation of failure with differential or % non-epithelial contamination. 1 The 233 samples were assessed by the established QC criteria and all those failing one or more were classified by which QC criteria were failed.
After calculating the Pearson correlation of each occasion with all other occasions, we considered the squared average of these correlations as the estimate of the most likely percent of true variance for which a single occasion could account.
We used the formula, where % σ T is the percent of true variance, r T is the Pearson correlation of each occasion with the total of all other occasions, and o is the number of occasions.
Four criteria support evidence of genetic influence on susceptibility to BD: peculiar geographical distribution, occasions of familial aggregation, correlation with class I HLA antigens (HLA-B51) and polymorphisms in genes that control immune responses [2, 7, 48, 49].
