In the regression models, survey year was entered first as a categorical variable to estimate differences between rounds; second, as a continuous variable to estimate an overall trend per year in the considered time period.
2
—
—
The sentences
Nevertheless, an increasing trend in psychological health complaints has already been observed in the last 20 years, especially among older girls, in Canada [ 18 ] and in several European countries, like Sweden [ 19 ], Norway [ 10 , 20 ], and the UK [ 21 ], while life satisfaction showed an unclear evolution [ 22 , 23 ].