['To assess changes in the mental and physical health of adolescents between the ages of 15 and 19.', 'The study included a four-year follow-up of 844 students from 31 secondary schools located in Kosice, Slovakia (response rate 45.6%). The 36-item short form (SF-36) scales were used to assess vitality and mental health, self-rated health, long-term well-being, long-standing illness, and the number of perceived health complaints at the age of 15 and four years later.', "Both boys and girls reported significant deterioration in vitality (mean difference boys 5.3; girls 3.3; P=0.001) and mental health (mean difference boys 7.7; girls 5.7; P=0.001), while only boys reported deterioration in self-rated health (P=0.047). The proportion of boys who reported an improvement ranged from 8%-40%, while the proportion of girls who reported an improvement ranged from 8%-45%. Significantly more girls than boys reported an improvement in mental health (27% of boys vs 34% of girls) and vitality (32% of boys vs 39% of girls), while more boys than girls reported a deterioration in vitality(55% of boys vs 48% of girls)). These differences were trivial according to the effect size (Cohen's H<0.20)."] Is deterioration the only prospect for adolescents ' health : improvement in self-reported health status among boys and girls from age 15 to age 19?