a significant trendP < 0.05
A significant trend was assumed where P < 0.05 using the Z statistic [ 37 , 39 ].
A significant trend was assumed where P < 0.05 using the Z statistic [ 37 , 39 ].
A positive value of tau (Kendall’s tau statistic) is an indicator of an increasing trend, whereas its negative value is indicative of a decreasing trend [ 38 ].