Phenotypic inter-factor correlations are shown in Table 2. The highest correlation was observed between Counting/Checking and Symmetry/Ordering (r = 0.70). Hoarding was less correlated with the other five dimensions (r = 0.31–0.52) and the TOCS total score (r = 0.57; Table 2).Table 2Factor–factor phenotypic correlationsOC trait dimensionsCleaning/ContaminationSymmetry/OrderingSuperstitionRuminationCounting/CheckingHoardingCleaning/Contamination1−−−−−Symmetry/Ordering0.62 0.59 1−−−−Superstition0.55 0.58 0.62 0.65 1−−−Rumination0.44 0.45 0.60 0.64 0.51 0.59 1−−Counting/Checking0.50 0.52 0.70 0.72 0.63 0.70 0.60 0.66 1−Hoarding0.31 0.29 0.45 0.52 0.42 0.47 0.34 0.49 0.52 0.56 1TOCS Total Score0.800.880.790.730.810.57p ≤ 0.01 for all valuesPearson’s correlation values between each of the six obsessive–compulsive (OC) trait dimensions. The values on the left show correlations in the whole sample (n = 16,718), and the bold, italicized values show correlations from the twin sub-sample (n = 220 pairs). TOCS = Toronto Obsessive–Compulsive Scale
