Impact study in Rotterdam

Research design

The research focused on assessing the social impact of the Invi Bracelet. Two main research questions guided the study:

  1. What is the effect of wearing the Invi Bracelet on feelings of safety?
  2. Is the Invi Bracelet a non-violent substitute for more aggressive self-defense tools?

Independent research partner Risbo (affiliated to the Erasmus University of Rotterdam) collected data through two detailed questionnaires.The first questionnaire (baseline measurement) was distributed among participants prior to wearing the Invi Bracelet, the second one after six weeks of wearing (follow-up measurement). A total of 83 participants completed both questionnaires. During a focus group (7 participants) the research questions were discussed in more detail.

Results & conclusions

Feeling of safety

The research findings show that the Invi Bracelet has a significant positive effect on a person’s feeling of safety. On average, respondents rated their feeling of safety 0.8 points higher when wearing the Bracelet, increasing from 6.6 to 7.4 (10 point scale). Figure 1 shows that the percentage of participants that sometimes feel unsafe strongly decreased (73% to 37%).

figure 1: percentage of respondents feeling unsafe

Subsequently, people who answered yes where asked how frequently they felt unsafe during the last four weeks. Figure 2 show that the percentage of people that often feel unsafe declined by more than half in the follow-up measurement. It also shows that people generally feel safer when wearing the Invi Bracelet. Observations from the focus group confirmed these findings. Overall people felt more confident and emphasized that the bracelet provided them with some sort of ‘peace of mind’. Many self-defense experts Invi has consulted emphasize that a strong and confident appearance can work as a ‘first line of defense’ and decreases chances of an assault.

figure 2: frequency of respondents feeling unsafe

The study also shows that some participants consider the Invi Bracelet as a non-violent substitute for more aggressive (e.g. knives) or illegal self-defense tools (e.g. pepperspray, which is illegal in the Netherlands). The follow-up measurement revealed that five out of nine participant chose Invi Bracelet as an alternative to illegal tools. Also a decrease of 39 percent in the use of more aggressive tools was found. Figure 3 shows the frequency of respondents carrying weapons or self-defense objects before and after the pilot period. Outcomes of the focus group highlight that participants particularly value the surprise effect of smell and the wearing convenience. Participants also liked the non-violent character of the Bracelet, as aggressive tools or weapons can result in more violent responses or can potentially be used against their owner.

figure 3: frequency of respondents carrying self-defense weapons or objects

During the pilot period, none of the participants found themselves in a situation that required activation of the Invi Bracelet.

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