Study design and ethical considerations
This study is a prospective cross-sectional study that sought to conduct a survey on the topic of human trafficking among refugees in a state registration and reception centre. It intended to assess the prevalence rate as well as sensitivity and specificity of the respective instrument. The study was approved by the local ethics committee (Ethics Committee, Medical Faculty of Heidelberg University, S249/2021; 05.05.2021) and was in line with the Declaration of Helsinki.
Sample Size and Power Calculation
To the best of our knowledge, no systematic study about the prevalence of trafficking among refugees within a registration and reception centre in Germany exists currently. Reports from the International Organization for Migration estimated in 2016 that about 80 percent of all Nigerian women and girls arriving by sea in Italy or other countries of the European Union were likely to be targeted for sexual exploitation (18). In 2017, the IOM reported that 37% of all interviewed migrants who had taken Mediterranean routes to Europe had personal experience indicating human trafficking (10). Therefore, we estimated the prevalence for trafficking survivors among refugees from various nations conservatively to be around 10%. Furthermore, the results of the AHTST and the single question by Mumma et al. (16) indicate that trafficking survivors differ significantly in their responses from non-trafficked persons. We therefore expected our questionnaire to have high sensitivity and followed the recommendations of (19) for the sample size: In their Monte Carlo study, they calculated that the ideal sample size with good expected sensitivity and a prevalence of 10% is at least 120 people.
Participants
Our target group were all refugees in the registration and reception centre who fulfilled our inclusion criteria. Inclusion criteria were an age of 18 or older and the ability to understand one of the following languages: Arabic, German, English, French, Farsi, Georgian, Kurmanji, Hausa, Pashto, Serbian, Somali, Turkish and, due to the high number of refugees fleeing from the war in Ukraine after March 2022, also Russian and Ukrainian. A total of 176 people took part in the study. Within our three gender categories, 35 (19.9%) identified as being female, 140 (79.5%) as being male and one (0.6%) person as being diverse. The average age was 30.9 years (SD = 8.2 years). 47.7% of the participants had children. As can be seen in Table 1, most participants came from West Asia and Central Asia. Accordingly, Arabic, Turkish and Farsi were the most commonly spoken languages and Islam the most common religion.
Table 1
Regions of Origin, Languages and Religion of all Participants (N = 176)
Region of Origin | Percentage |
West Asia | 38.1 |
Central Asia | 17.6 |
East Europe | 16.5 |
West Africa | 13.6 |
North Africa | 11.4 |
East Africa | 1.1 |
Bahamas | 0.6 |
Unknown | 1.1 |
Language | Percentage |
Arabic | 25.0 |
Turkish | 19.3 |
Farsi | 16.5 |
English | 14.2 |
Georgian | 10.2 |
French | 7.4 |
Russian | 2.3 |
German | 2.3 |
Serbian | 1.7 |
Pashtu | 0.6 |
Ukrainian | 0.6 |
Religion | Percentage |
Islam | 66.5 |
Christianity | 25.6 |
Atheism | 3.9 |
Alevis | 1.1 |
Hinduism | 0.6 |
Other | 2.3 |
Note. The allocation of individual countries to regions is found in the supplement. The order is based on the percentages. |
---------------------------------------- Table 1about here -------------------------------------------------
Setting
The Patrick Henry Village Heidelberg (PHV) is where asylum-seekers are registered for the first time in the state of Baden-Württemberg. It usually accommodates between 1200 to 2400 newly arrived asylum-seekers. During their stay at PHV, state employees verify their identity, register their personal data and carry out a medical examination for communicable diseases as part of the asylum procedure. After around five weeks, asylum-seekers are redistributed to communal accommodations.
Development of the screening tool
In our study, we used a combination of the eight questions of the AHTST (15) and the single question about abuse which was developed by Mumma et al. (16). The AHTST applies to different forms of human trafficking while the screening questions by Mumma et al. (16) originally aimed at the identification of victims of sex trafficking in the emergency department but was so accurate in the original publication that we included it in our questionnaire (see Appendix A). We considered both valuable instruments for all forms of exploitation that were trauma-informed and culturally sensitive, which we assumed to be especially important for our sample of refugees. For each of the presented items, there were four answer categories: “Yes”, “No”, “Don’t know”, and “I Decline to answer”. Other than in the U.S. population, for which the original version of the AHTST was created, we expected a threshold of one positive answer as too low for our context, as most asylum-seekers experience similar forms of violence outside of a trafficking situation (20). We translated the English version into eleven other languages (Arabic, Farsi, French, German, Georgian, Hausa, Kurmanji, Pashto, Serbian, Somali, Turkish), and when the numbers of Ukrainian refugees increased in March 2022, we also provided a Russian and Ukrainian version of our study.
Data Collection
The study took place during the Covid-19 pandemic in late 2021 until summer 2022. During the first four months of the study, all participants had to remain under quarantine for ten to twelve days due to pandemic requirements. During their fifth to eighth day of isolation, when they were already tested negative but were only allowed to step out a few meters outside, we spoke to the participants in front of their accommodation. From March 2022 onwards, the quarantine for refugees wasn’t obligatory anymore, so they were free to go outside anytime. The screening was restricted by specific precautions, such as wearing a mask or keeping a distance of two metres between participants and two female researchers. The researchers approached one accommodation at a time and asked the participants to meet them outside one by one in order to lower the risk of infections. There, the following data was collected:
Demographic information and screening tool
In this phase, participants used a tablet that the researchers provided. They completed several demographic questions concerning their age, gender, country of origin, religion, and parenthood. Next, participants filled out the Adult Human Trafficking Screening Tool followed by the central question found in Mumma et al. (16), as described earlier.
Verification of human trafficking
Independent from their answers provided in the screening tool, every participant answered five additional questions about indicators for human trafficking. In this short semi-structured interview, we cross-checked whether a participant had experienced trafficking according to the questions below about working hours, imprisonment, control over payment, experiences of violence and debt. The researcher posed the following questions with the support of a multilingual neural machine translation within five to ten minutes.
-
Have you ever been in a situation where you had to work for long hours every day without any day off?
-
Have you ever been in a situation where you worked in a house that you were not allowed to leave?
-
Have you ever worked and someone else was in control of your income?
-
Have you ever been in a situation where you or someone you worked with was beaten and made feel pain for working slowly or trying to leave?
-
Have you ever been forced to work because you felt you were bonded by debt?
Participants that described trafficking experiences were invited to present themselves at a psychosocial walk-in clinic (21) or at the local counselling service. If the trafficking survivors gave their consent, the researchers reached out to the local specialised counselling centre for trafficked people, social workers within the state registration and reception centre, and the coordinator for accommodation of asylum-seekers of vulnerable groups.
Data Analysis
All calculations were performed with Microsoft Excel 2019. We first added up how many questions the participants answered with "Yes". Then, for each possible cut-off of one to nine "Yes" answered questions, we calculated how many True Positive, False Positive, True Negative, and False Negative results the questionnaire yielded. With this, we calculated the sensitivity, specificity, positive predictive value, negative predictive value, correct classification rate, and positive likelihood ratio of the questionnaire. The choice of the final cut-off was based on several principles: Since the group of people who did not experience human trafficking was expected to be larger, we aimed at a cut-off that would generate as few false positives as possible. At the same time, the cut-off, if it were to indicate a positive result, should be relevant and clearly indicate human trafficking. We therefore also chose the cut-off with the highest possible relevance and positive likelihood ratio. As described in the introduction, the West African subregion is the non-European region of origin with the highest contribution to trafficking flows into Western and Southern Europe (6). We therefore decided to conduct an additional exploratory analysis comparing West African participants with the rest of our sample. Because only 24 of 176 participants were from the West African region, this analysis resulted in a particularly uneven sample size. Since this uneven sample size did not provide enough power for significance testing, the comparison was descriptive.