Introduction

Emergency medical services (EMS) is an organized system, which plays a key role in providing pre-hospital treatment and transferring sick or injured patients to medical centers [1]. While EMS’s resources are constrained, there are numerous and growing demands for its services worldwide [2-4]. Furthermore, excessive use of EMS would lead to overcrowding in emergency departments which is a serious issue by itself [5]. Therefore, improper utilization of EMS may endanger the lives of some patients [6, 7].

It is likely that, inappropriate use of EMS is a major global issue. Several reports of “unnecessary ambulance use” were received from England, Australia, Canada, and South Africa [8]. Reports indicated that between 16-51.7% of calls were found to be improper [8]. Nevertheless, defining the “appropriate” use of EMS is still very challenging [9]. Inappropriate use of EMS usually occurs when non-emergent cases ask for EMS transport, or when such patients have an alternative means of transportation to ED but choose EMS instead [8, 10, 11]. Previous studies revealed that race, age, educational degree, healthcare background, and prior first-aid training are all strongly associated with this misuse [8]. Moreover, the caller’s background is important when determining whether a call is inappropriate. Inappropriate calls are caused by a lack of knowledge, as well as the fact that the majority of these callers believe that using an ambulance and EMS is the safest and fastest way to get to the hospital [12]. It was reported that prior training regarding basic first aid procedures may also have a significant impact on reducing the increasing number of inappropriate calls [8].

Iranian researchers conducted several [13, 14] studies on this issue, and they concluded that it is critical to deliver instructional programs regarding EMS duties, particularly for people who lived in lower socioeconomic areas [13]. Furthermore, other researchers found that most people were unaware of emergency medical conditions and the description of EMS duties, which leads to calling the EMS for non-urgent missions [14]. Despite some recent studies, there is still a paucity of information regarding the level of public awareness of emergency situations and reasons for calling the EMS. Meanwhile, in recent years, there has been a significant increase in requests to use EMS [15-17]. Therefore, we aimed to investigate the level of public awareness of emergency situations and possible influencing factors for contacting EMS.

Materials and Methods

This cross-sectional study was conducted from August 2021 to January 2023 in Tehran, Iran. A questionnaire was prepared to assess public awareness about which medical circumstances they think are appropriate to contact EMS. To prepare the questionnaire, Tehran EMS dispatch archive from a year prior to the implementation of the study was evaluated. A technical committee designed 24 scenarios based on the most common frequent cause of contact. The committee consisted of members of the research team, one supervisor from the EMS center, one quality control specialist, a representative from the research section of Tehran EMS center, and an epidemiologist. Some modification was made based on available references as well as the committee members’ personal experiences. In the next step, the face validity and content validity of the questionnaire for clarity, relevance, and comprehensiveness, based on the opinions of 10 experts and people with opinions on the subject under study, were examined. Then, the questionnaire was modified based on their comments. The relevance and clarity of the questionnaire were measured by both the item-level (I-CVI) and the scale-level content validity index (S-CVI), while only the S-CVI was used to determine the comprehensiveness of the questionnaire. For the content validity index (CVI), the validity indices higher than 0.80 were considered acceptable. In addition, the content validity ratios (CVR) were calculated and assessed based on Ayre and Scally’s revised method [18]. Finally, the reliability of the questionnaire was assessed and confirmed using Cronbach’s alpha analysis in a pilot study with 30 persons from the target population. The final questionnaire is presented in Table 1. For each scenario, the questions included four options:

1- It’s an emergency, I will call EMS.

2- It’s an emergency, but I won’t call EMS.

3- It is not an emergency, and I won’t call EMS.

4- It is not an emergency, but I will call EMS.

All people over the age of 18, who had called Tehran EMS with a legitimate phone number during a year prior to the implementation of the study, were eligible to participate in the study. No additional restrictions (such as age and sex) were implemented. Participants who did not complete their questionnaires were excluded from the study. Tehran EMS carried out around 350,000 missions during the year preceding the beginning of this study. The minimum required sample size was 10% of the target population, which was equivalent to 3,500 people.

An invitation for completing the questionnaires was sent to the target population via an SMS link, and the participants were directed to an online survey link. Considering the probability of a 5% participation rate, this SMS was sent to 700,000 individuals. All participants were identified using their telecommunication prefix and placed in a random cluster in each region. To obtain information about the characteristics of the participants, several demographic questions before the scenario questions were asked. The participants were asked to indicate their preferred options for the predetermined scenarios. We divided the participants into three groups, including those who continued to call EMS despite being aware of non-emergency conditions (abuse), those who called EMS in non-emergency conditions due to lack of knowledge (misuse), and those who did not call EMS despite being aware of emergency conditions (not-use). At least 12 correct answers were required to qualify as acceptable knowledge and practice (KP) responses. This cut-off point was determined based on the consensus of the experts, which was equal to the minimum correct response to half of the questions. The level of awareness was investigated based on the participant’s location, sex, ethnicity, age, level of education, average income, occupation, marital status, and history of previous use of emergency services. Then, the relationship between these variables and the level of public awareness was investigated.

Statistical Analysis

Data were analyzed using IBM SPSS Statistics software version 25.0 (IBM SPSS Inc., Chicago, IL, USA). Numerical variables were expressed as mean±SD (standard deviation) and categorical variables as numbers and percentages. The independent sample T-test was used to assess mean differences in numerical variables. A p-value ≤0.05 was considered statistically significant. Additionally, univariate and multivariate logistic regression were used to identify potential factors associated with correct knowledge regarding the scenarios.

Results

The data of 3864 people were analyzed. 49.5% of the participants were female (49.5%). The mean age of the patients was 40.01±11.30 years, ranging from 18 to 90 years. Furthermore, 29.7% of the participants had a master’s degree or higher, 64.6% were employed, 63.0% were Fars, and the rest were from other ethnic groups. Females had significantly higher mean correct KP scores than males (12.5 vs. 12.1; p<0.001). Additionally, there was a significant correlation between the right KP score and education, academic background, employment, and income (Table 2).

In general, despite being aware of non-emergency conditions (abuse), 74.5% of people still called EMS for at least one of the 24 designed scenarios, which ranged from 5.5% to 28.5% for different scenarios. On the other hand, 70.4% of the participants did not call EMS for at least one scenario despite being aware of emergency conditions, which ranged from 4.1% to 26.7% for different scenarios. In general, 64% of people called EMS for at least one of the 13 non-emergency scenarios, due to lack of knowledge of emergency conditions (misuse), which varied between 6.7 and 9. 48% for each scenario (Table 3).

The scenarios “A 4-year-old boy has taken ten acetaminophens (500 mg) tablets” and “Your 10-year-old son develops hives while playing at a family picnic” had the highest and lowest correct knowledge and practice scores of 86.1% and 11.1%, respectively. Moreover, the scenarios “A 77-year-old person has difficulty speaking and speaks indistinctly (like a drunk). He or she has not consumed any alcohol or drugs” and “A 40-year-old man with a history of colon cancer has severe pain and needs painkillers” had the highest and lowest correct knowledge and practice scores of 95.3% and 37.0%, respectively (Table 3).

Univariable logistic regression analysis showed that lower ages, female sex, higher education, the academic field of medical sciences, employed job status, and high income were associated with acceptable correct knowledge and practice answers (KP score>12). According to the multivariable regression analysis, female sex (OR=1.29), M.D/Ph.D and higher education (OR=3.36), higher income level (OR=1.64), and Turkish ethnicity (OR=1.20) were all significantly associated with an acceptable KP score (Table 4).

Discussion

In this study, the data from 3864 participants reflects their awareness regarding emergent situations and whether or not they call an ambulance for transporting their patients to the hospital. To the best of our knowledge, this was the largest study to date in terms of the number of survey respondents. Furthermore, we assessed each participant’s knowledge using a comprehensive set of medical scenarios to address all probable circumstances that one could confront throughout their life. We evaluated several factors that could affect one’s knowledge including, age, sex, marital status, household member, educational degree, previous academic education in the field of medicine, employment status, income, and ethnicity. The univariable analyses showed that the age of 26-45 years old, female sex, having a diploma or higher level of education, studying in the field of medicine, being employed, and having higher income were all significantly associated with correct KP scores. This association was still significant after performing a multivariable analysis for sex, education, income, and ethnicity. The scenarios “A 4-year-old boy has taken ten acetaminophens (500mg) tablets” and “Your 10-year-old son develops hives while playing at a family picnic’ had the most and least correct KP answers, respectively.

Few studies were conducted to assess public awareness regarding the correct use of EMS in emergency situations that required ambulance presence. Mills et al., contacted 544 Australian individuals to complete a 17-scenario questionnaire and found that there was a lack of knowledge among Australian participants particularly among those without first-aid training [11]. They showed education, previous healthcare experience, and age were significantly associated with accurately answering the scenarios, which was consistent with our findings. In contrast to our findings, there was no association between sex and the correct answer to the scenarios. Moreover, Kirkby et al., found that female participants made more inappropriate calls with an odd of 5.96 [8].

Previous first-aid training was shown to be positively correlated with public awareness regarding appropriate EMS calls [11]. Unfortunately, we did not exactly assess this factor in our study; however, we found a significant association between prior academic education in the field of medicine and higher KP scores.

In our study, among scenarios that required an ambulance, only two scenarios had less than 50% of participants responding correctly, including “Your two-year-old child has symptoms of a cold and is drooling from the corner of the mouth while crying, his voice is hoarse and the area around his lips is bruised” with 34.5% and “Your 10-year-old son develops hives while playing on a family picnic” with 11.1%. One possible explanation for this could be the participant’s different interpretations of the case and a lack of knowledge about these medical scenarios. Previous studies did not assess these scenarios [13, 14], therefore, there was a lack of knowledge about how other nations dealt with these unexpected issues. Furthermore, it seems that increasing awareness about emergent situations which need the attendance of an ambulance for diabetes and head trauma is mandatory. Since a large number of our participants did not seek EMS assistance in scenarios 5 and 7.

Among those scenarios which did not require an ambulance, none of the scenarios had more than 50% of participants responding that they would seek an ambulance by calling EMS. The two scenarios “An 8-month pregnant woman feels that the fetal movements are not normal” and “A four-year-old child inserted a small toy in her ear” had the highest percentage of inaccurate ambulance calls. Similarly, previous studies reported misdiagnosis of labor as an emergent condition requiring an ambulance call [8, 11, 19]. In the study by Kirkby et al., nearly 50% of participants believed that labor delivery was an emergent condition. In the present study, more than 60% of the participant believed that this was an emergency condition, and about 40% decided to call EMS. Foreign object in the ear was another scenario that most people misinterpreted as an emergent situation. Mills et al., reported that all of the participants decided to call EMS. We also found that 1889 out of the 3864 participants would call EMS in the aforementioned situation.

The present study evaluated the scenarios that represented stroke, myocardial infarction, drug overdose, and epilepsy. Fortunately, the participant’s awareness of the necessity to seek an ambulance when facing these situations was acceptable. However, a greater emphasis on raising awareness of the urgency of these conditions would be extremely beneficial. One of the remarkable findings reported by Mills et al., was that the Australian participant identified stroke as an emergent situation, yet they decided to transport their patients personally rather than waiting for an ambulance. In our study, nearly 88% of participants recognized this scenario as an emergency, and 84% decided to call EMS.

The present study has several strengths. To the best of our knowledge, this was the largest study conducted on the participants’ awareness of what medical circumstances would prompt the participants to call for an ambulance. Second, we presented a comprehensive set of scenarios (24 scenarios) using the experience of both paramedics and emergency medicine specialists. Third, we used both univariable and multivariable logistic models to examine several factors associated with the odds of individuals providing correct answers. It also had some limitations. Although the present study included large sample size, it was not a nationwide study, and we only evaluated responses from the residents of Tehran. Since the majority of our participants were educated and limited information was available about those who were not; therefore, our findings cannot be generalized when applied to real-world experiences.

The amount of incorrect use of EMS services in Iran was significant. We found that the proper knowledge regarding the appropriate use of EMS was significantly associated with the participant’s level of education, academic field, occupation, and income. Public awareness campaigns can implement the findings of our study to prioritize which scenarios should receive greater attention. Moreover, further studies, particularly a nationwide study on the Iranian population regarding this topic are highly recommended.

In addition, considering the high percentage of people who called EMS despite being aware of non-emergency conditions, it is suggested that a study be designed to investigate the causes of abuse to reduce the burden of unnecessary calls by identifying and modifying these factors that may lead to an increase in EMS performance quality.

Declaration

Ethics approval and consent to participate: The study protocol was approved by the ethics committee Tehran University of Medical Sciences Institutional Review Board (IR.TUMS.SINAHOSPITAL.REC.1400.051). To maintain the confidentiality of the personal information of the participants, all information was collected, analyzed, and reported anonymously. All participants were included in the study if they expressed their informed consent.

Consent for publication: All authors have expressed their consent to the publication of this manuscript.

Conflict of Interest: The authors declared that there was no conflict of interest.

Funding: There is no funding support for this study.

Authors’ Contribution: The conception and design of the work by all the authors; Data acquisition by AS, PHS, and AB; Analysis and interpretation of data by HR and AB; Drafting the work by PS and AS; Revising it critically for important intellectual content by PHS, HR, and AB; All the authors approved the final version to be published; and agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work.

Acknowledgment: We would like to express our commitment and appreciation to the Prehospital and Hospital Emergency Research Center affiliated with the Tehran University of Medical Sciences (Tehran, Iran).