User's guide to correlation coefficients
www.ncbi.nlm.nih.gov › pmc › articlesAug 07, 2018 · A statistically significant correlation does not necessarily mean that the strength of the correlation is strong. The p-value shows the probability that this strength may occur by chance. In the dataset shown in Fig. 1, the correlation coefficient of systolic and diastolic blood pressures was 0.64, with a p-value of less than 0.0001. This r of 0.64 is moderate to strong correlation with a very high statistical significance (p < 0.0001).