Introduction: When treating stroke patients, the aim should be to get the patient to a specialist stroke centre as soon as possible. Objective: In our study, in order to be able to stay within the therapeutic window, we investigated which variables affect the time period of prehospital treatment. Method: For our cross-sectional quantitative study, we gathered data from two ambulance stations in Hungary, comparing the competence of physician and non-physician units. We processed information from 2017 regarding patients whose initial diagnosis was stroke (n = 220). We examined how investigations by the ambulance unit, symptoms experienced and therapeutic time window have affected prehospital times. As for the statistic software, we used SPSS 26.0. The analysis was conducted by performing χ2 test, F-test and T-test. Results: We identified that if the aphasia component of the used score system was positive, the on-scene time increased significantly (p = 0.003). In the D section of the rapid ABCDE assessment, it is mandatory to measure the blood glucose level of the patient, however, in our sample it was omitted in 25.45% of the cases. We identified that on-site blood glucose measurement has an effect on prehospital delay for non-physician units (p<0.001). Conclusion: We found that the on-scene time is longer for physician units than for non-physician units. We concluded that motor or sensory aphasia does not affect the therapy, it is just one of the symptoms that can increase the likelihood of stroke diagnosis, therefore prolonging time for assessing aphasia in the field should be avoided. Moreover, it is recommended to make care providers aware of this during training sessions. Improvements are required in non-physician units to reduce the time consumed by blood glucose measurement, as it has been shown that within physician units this test does not appear to be a delay-causing factor. Orv Hetil. 2022; 163(7): 279–287.