## 4 Results
### Constructs and Methodological Approaches
#### 4.3.4 Interaction Behavior, Drowsiness/Fatigue, and User Experience  
Participants' _interaction behavior_ with AV/ADS was mainly investigated by behavioral data (n\({}_{\text{p}}\) = 11), observing (n = 6) such as pedestrians' walking behavior, number/share of times the automation was activated/deactivated, or eye-tracking analysis (percentage of the gaze on different AOIs). However, standardized questionnaires (n = 3) like the Pedestrian Behavior Questionnaire (PBQ) [106], Brief Sensation Seeking Scale (BSSS-8) [107] or the theory of planned behavior (TPB) [108] were also used. Two papers developed an own questionnaire, and one paper applied eye-tracking, conducted an interview or collected data on secondary task performance, see Table 9. In total, n\({}_{\text{p}}\) = 13 different parameters were collected across all papers investigating interaction behavior--45% studies regarding interaction behavior were investigated in a driving simulator, 36% used a Wizard-of-Oz setup, and 27% a real vehicle. \begin{table}
\begin{tabular}{l l l} \hline \hline
**Collection Method for Stress (n)** & **Parameter** & **n\({}_{\text{p}}\)** \\ \hline \multirow{4}{*}{Standardized Questionnaire (6)} & Short Stress State Questionnaire (SSSQ) & 3 \\ \cline{2-3}  & Dundee Stress State Questionnaire (DSSQ) & 2 \\ \cline{2-3}  & Driver Stress Inventory (DSI) & 1 \\ \hline \multirow{4}{*}{Heart Rate Variability (4)} & HR (BPM) & 2 \\ \cline{2-3}  & Physical Position & 1 \\ \cline{2-3}  & Root Mean Square of Successive Differences (RMSSD) & 1 \\ \hline \multirow{4}{*}{GSR (2)} & AmpSum & 1 \\ \cline{2-3}  & ISCR & 1 \\ \cline{2-3}  & nSCR & 1 \\ \cline{2-3}  & SCR & 1 \\ \cline{2-3}  & PhasicMax & 1 \\ \cline{2-3}  & _N/D_ & 1 \\ \hline \multirow{2}{*}{Eye Tracking/Gaze Behavior (1)} & Gaze Duration & 1 \\ \cline{2-3}  & Gaze Number & 1 \\ \hline Self-Defined Questionnaire (1) & Other & 1 \\ \hline Observation (1) & Body Pose/m Movements & 1 \\ \hline Interviews (1) & Semi-structured Interview & 1 \\ \hline EMG (1) & _N/D_ & 1 \\ \hline Driving Performance (1) & Automation Enabled/Disabled & 1 \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Stress collection methods and parameters. _Drowsiness/Fatigue_ was investigated by self-reported (\(\text{n}_{\text{p}}=11\)) and behavioral data (\(\text{n}_{\text{p}}=7\)). Hence, standardized questionnaires (n = 7) like Karolinska Sleepiness Scale (KSS) [109], Driver Stress Inventory (DSI) [110], Multidimensional Fatigue Inventory (MFI) [111] are mainly used as well as self-developed questionnaires (n = 2). However, researchers also collected (n = 2) blinking behavior or yawing, as well as eye-tracking, driving performance or adapted the method of UX Curve [112]. See Table 10. In total, \(\text{n}_{\text{p}}=12\) different parameters were collected across all papers investigating drowsiness/fatigue--91% of the studies collecting drowsiness were conducted in a driving simulator, 9% used a real vehicle, and a further 9% used static text as AV representation. \begin{table}
\begin{tabular}{l l l} \hline \hline
**Collection Method for Drowsiness/Fatigue (n)** & **Parameter** & \(\text{n}_{\text{p}}\) \\ \hline \multirow{7}{*}{Standardized Questionnaire (7)} & Karolinska Sleepiness Scale (KSS) & 4 \\ \cline{2-3}  & Driver Stress Inventory (DSI) & 1 \\ \cline{2-3}  & Multidimensional Fatigue Inventory (MFI) & 1 \\ \cline{2-3}  & Self-Assessment Manikin (SAM) Scale & 1 \\ \cline{2-3}  & Dundee Stress State Questionnaire (DSSQ) & 1 \\ \hline Self-Defined Questionnaire (2) & Other & 2 \\ \hline \multirow{7}{*}{Observation (2)} & Yawning & 1 \\ \cline{2-3}  & Blink Behavior & 1 \\ \cline{2-3}  & N/D & 1 \\ \hline \multirow{7}{*}{Driving Performance (1)} & Reaction Time & 2 \\ \cline{2-3}  & Lateral Position & 1 \\ \cline{2-3}  & Eye Tracking/Gaze Behavior (1) & Glancing Behavior & 1 \\ \hline UX-Curve (1) & N/D & 1 \\ \hline \hline \end{tabular}
\end{table} 
Table 10: Drowsiness/Fatigue collection methods and parameters.