Table 1.

Dosage of oral vitamin D3 in the present population with respect to all individual determinations of prospective vitamin D3 dose after having received the laboratory results.

	All Patients (n = 319)	MS Patients (n = 74)	Non-MS Patients (n = 245)
Number of laboratory investigations	1606	387	1219
Minimum/Maximum of daily vitamin D3 dosage (IU per day)	0/150,000	0/150,000	0/100,000
Mean dosage of daily vitamin D3 (IU per day ±SD)	35,291 ± 21,791	52,955 ± 25,791	29,683 ± 16,861
Spearman correlation dosage vitamin D3 and serum calcium	0.103, p < 0.001 n = 1204	0.151, p = 0.010 n = 291	0.050, p = 0.128 n = 913
Spearman correlation dosage vitamin D3 and urinary calcium excretion	0.162, p = 0.001 n = 433	0.058, p = 0.456 n = 166	0.233, p < 0.001 n = 267

In total, the 319 patients were subjected to 1606 laboratory investigations. The current dosage of oral vitamin D3 was either maintained or adapted after each of these investigations. The correlations presented in this table represent the Spearman correlations between the currently agreed upon dosage of oral vitamin D3 and the serum/urinary calcium levels measured at the subsequent laboratory follow-up, broken down by MS and non-MS patients. As the table shows, although some of the observed correlations are significantly different from zero (mostly due to the large sample size), all of them are moderate in terms of their absolute numerical value. In our sample, we thus only find a very weak relationship between the dosage of oral vitamin D3 and the subsequent calcium levels, both in serum and in urinary excretion.