➢This was a cross-sectional, retrospective study with an analytical focus.

➢Population:

· Primary targets:

The sample population is made up of all the accident files recorded in the six (06) districts randomly selected from the thirteen (13) districts of Cotonou.

The process of drawing lots was as follows:

We wrote on a piece of paper Cotonou’s 13 districts and we drew 6 districts without discount.

· Secondary targets:

The source population for this target is all the staff members having observed accidents in the six (06) districts randomly selected.

➢Inclusion criteria:

Primary targets:

• Was included the accident official reports.

• Report cards for the analysis of recorded accidents developed.

Secondary targets:

Be a police officer who has made at least one accident report since joining the Precinct.

➢Non-inclusion and exclusion criteria:

Primary targets:

• Accident report not yet prepared.

• Accident Analysis official Report Form not yet prepared.

• Unreadable accident analysis form.

Secondary targets:

Be a police officer with no prior record of accidents since joining the Precinct.

Was excluded for this study any unreadable accident report.

Methods and techniques for sampling of Official Statements of Offence (OSI) and reporting officers in Cotonou in 2019. Table 1 gives the synthesis of methods and techniques for sampling.

All respondents were informed of the nature and objectives of the study. In addition, the following ethical rules were observed:

Free and informed consent was obtained from the police commissioners before the survey was conducted. The police units interviewed were informed of the use that is made of the information collected.

Anonymity: The interviews and questionnaires were conducted anonymously. No names were disclosed during the study.

Confidentiality: the information obtained is used only within the strict boundaries of this work and no one was negatively affected by the use of collected data.

The representation of accidents recorded with GPS is as follows in Figure 2.

By enlarging the map above, we can see that some crash points were off the road despite the 7 m margin related to the GPS accuracy. These poorly represented accident points are 15 out of a total of 156 geolocated accidents, so

the percentage of poorly represented accidents in our sample is 9.62% with a confidence interval ranging from 5% to 14.25%.

Observing the resulting map also revealed that most of the road accidents occur after the crossroads “Etoile-rouge”. Thus, the road network (National Interstate Highway Number 2 and urban roads) extending from the Etoile-Rouge intersection to Tokpa has a high density of accidents compared to the road network extending from Menontin to the Etoile-Rouge intersection.

The aim of this work was to study the factors associated with the geolocation of public road accidents in Cotonou in 2019. The major outcomes of this study are as follows.

- the prevalence of accidents that were geolocated in 2019 was 41.62%.

- factors associated with the geolocation of public road accidents were: the level of education, the means of travel, the level of severity of the accident and the type of day on which the accident occurred.

- The quality of the coordinates provided: about 15% of the coordinates collected during the accident reports in Cotonou are of poor quality (85% are of good quality).

We thus consider that the objectives of the study have been achieved.

In order to achieve our objectives, the study was conducted cross-sectionally. Among other things, this study will enable us to calculate the rate of use of GPS in public road accidents. The sampling method was probabilistic and the technique of random choice. Our study was cross-sectional and analytical. The probabilistic method and the random sampling technique were used. This approach was possible thanks to the processing of 384 files randomly selected in the 06 districts (1, 3, 6, 8, 10, 11) of recorded accidents. The size of our sample was calculated using the Schwartz formula.

The questionnaire was administered in the local language or in French depending on the respondent. Logistic regression was used to search for the association with a p-value ≤ 0.05. In order to better explain the studied phenomenon, we conducted interviews with the police officers. For data analysis, we used multiple logistic regression at the 5% threshold. The type of study chosen could not identify the real factors associated with the use of GPS in crashes. The temporal sequence between exposures and events is difficult to establish in cross-sectional studies, which might have been possible with a longitudinal study. However, this study provided results that can be used to conduct interventions for this target and could serve as a basis for further studies on a national scale.

Like any cross-sectional study, our study could also be subject to selection and information bias. Selection bias could be related to the likelihood of nonresponse or refusal to participate in the survey.

The data used in our study were obtained in a cross-sectional manner by document and questionnaire analysis. Several pieces of information called upon the memory of police officers. These items could introduce information bias. However, we tried to minimize these biases by:

- trying to ask the questions in stages and asking for the same information from multiple viewpoints, overlaying them to see discrepancies and re-specifying information as needed;

- briefing interviewers on the tools and;

- pre-testing tools to adapt them and ensure a common understanding of their content by all interviewers.

In addition, all the free and informed consent of the respondents and the various ethical provisions were taken during the collection. In light of all this, we believe that our results are valid and reliable.

The best way is to take all the accidents that were recorded in 2019, but given the time available for collection, we had set up a sample.

At the end of this study, the frequency of information on the coordinates of accidents in Cotonou is estimated at about 42% of cases.

This proportion in Cotonou was relatively encouraging when one considers that the use of GPS coordinates to locate accidents was at the beginning of its expansion throughout the world, but was not yet systematically available. Nevertheless, it is lower than that reported by El-Mansouri and Fournier, which was 70% [6]. It must be recognized, however, that not all districts have the same frequency of accidents. This point was also made in the study by Sounkayna and Fournier [6]. Regarding the quality of GPS coordinates, 85% were of good quality in Cotonou. This contradicts the results of the Cooperative Research in Road Safety of the University of Sherbrooke, according to which more than 70% of the GPS coordinates recorded during accidents are not exploitable [7].

This study found that most of the officers who perform these observations have a high school education, although this does not influence the report by GPS as much as those with a higher education level. The higher the level of education, the more likely it is that the officer is able to use the GPS. Most of them were first- and second-class police officers, but it was the brigadier police officers who were more able to report by GPS. The means of travel used to access the scene of the accident is a determining factor in the taking of GPS coordinates. These officers have been trained and are regularly monitored even after training in the proper use of GPS. In the majority of cases the accidents causing property damage were found without GPS coordinates. In contrast, it can be seen that as soon as the accident is fatal, it is more likely to be geotagged than a simple material accident (Table 8). This could be understood from the point of view of the importance of the accident which would be linked to multiple legal proceedings. Our study found that accidents that occurred on days with no special circumstances had a higher chance of being geotagged than those that occurred on market days, holidays and weekends. This can be explained by the fact that the days without any particularity are mainly the days when the police officer is not overwhelmed with tasks and can therefore validly execute all the procedures related to accident reports.