“…Studies using both self-reports and physiological measures were the most common (33 articles [ 37 , 65 – 67 , 72 , 73 , 87 , 90 , 91 , 94 , 96 , 98 , 101 , 106 – 125 ]; 37.5%), followed by articles solely relying on either self-reports alone (30 articles [ 56 , 60 , 63 , 64 , 68 , 70 , 71 , 84 , 92 , 95 , 99 , 102 , 103 , 126 – 142 ]; 34.1%) or physiological measures alone (19 articles [ 55 , 62 , 69 , 79 , 86 , 88 , 89 , 93 , 143 – 153 ]; 21.6%). There were two articles [ 100 , 154 ] (2.3%) that used behavioural analysis in addition to self-reports and physiological measures. Heart rate or heart rate variability-related instruments were the most common (32 articles [ 65 , 67 , 69 , 79 , 86 – 90 , 94 , 96 , 98 , 100 , 106 – 111 , 113 , 114 , 117 – 120 , 124 , 143 , 145 , 148 , 151 , 152 …”