What is the Bystander Effect?

The bystander effect refers to a psychological phenomenon in which individuals are less likely to offer assistance to a person in need when there are other people present. Essentially, the presence of other bystanders can lead to a diffusion of responsibility where each person assumes that someone else will take action, resulting in a delay or absence of help. In the context of Sudden Cardiac Arrest (SCA), bystanders may refrain from dialing 911, offering CPR, or using an AED on the person in need.  

Common Reasons for Bystander Hesitancy

Diffusion of Responsibility

One common reason for the bystander effect is a principle known as the diffusion of responsibility. This is a misguided tendency of individuals to expect others to be better suited to step in and help. This way, the individual feels less personal responsibility towards the person in distress.

It is always best to assume that nobody else has called 911 and take that immediate and simple action if you ever witness an emergency. Don’t be afraid to call 911! Dispatchers are trained to help you by providing lifesaving instruction over the phone.

Fear of Negative Repercussions

Another reason why the bystander effect happens is fear an intervention may be interpreted as inappropriate. For example, men may hesitate to give CPR to a women because it involves contact with her breast area, and they fear that this may be seen as lewd. Bystanders may be afraid to remove a woman’s shirt and bra in order to perform CPR and attach an AED’s electrode pads to her chest for fear of inappropriately exposing her bare chest. (Normalizing this part of the rescue scenario for female victims is part of the reason why the Avive Connect AED audibly instructs AED users to Expose the patient’s bare chest, including bra.) It is critical to normalize CPR and AED use on women since exposing a person’s chest in an attempt to save their life is necessary.

What many don’t understand, is that a person in cardiac arrest is already dead. Any action that someone attempts to take, only has the potential to help the person in distress.

Drawing upon research, one study showed that those wearing bras were less likely to receive effective AED treatment. A 2015 study conducted by Canadian psychologists at the Universities of Laval and Calgary found that only 42% of participants removed the manikin’s bras as required for proper AED use.

A potential responder may also be afraid they do not possess the right skills and could inadvertently make the situation even worse. Witnesses of a medical emergency often fear that they may be subject to blame or legal action if they are perceived to have caused harm to the victim when trying to help them. However, the law actually encourages lay people and bystanders to perform CPR and to use an AED on people who have suffered from SCA and it actually protects them from litigation.

Gaps in Preparedness- Race & Ethnicity

The element of race and ethnicity can also play a role in influencing bystander willingness to help. Alarmingly, in public spaces, Black people are just HALF as likely as white people to receive bystander help during medical emergencies.

One study found a direct relationship between the median household income and racial composition of a neighborhood and the probability that a person in need would receive bystander CPR. The study cited the cost of CPR training, a lack of outreach to minority neighborhoods by organizations that promote CPR, language barriers, and cultural issues around learning and performing CPR as some reasons for the disparity. 

Other studies have shown that individuals who suffer SCA in predominantly Latinx neighborhoods were also less likely to receive bystander CPR and had a lower likelihood of survival. These findings suggest an important need to understand the underlying disparities in CPR delivery and the unmet CPR and AED training needs among Latinx communities.

Fear & Misinformation

Bystanders may also hesitate to initiate CPR and use an AED on a SCA victim because of misinformation, such as fear that they could apply an excessive shock and kill the victim. In this case, lack of public awareness around AEDs and SCA becomes life-threatening. AEDs will automatically analyze the patient’s heart rhythm and will only deliver a shock if the rhythm is determined to be one of two heart rhythms deemed shockable.

AEDs will not provide a shock to anyone who is not in a fatal heart rhythm. AEDs are safe and specifically designed to be used by lay persons with little to no medical training.

The Importance of Bystander CPR

Out-of-hospital cardiac arrest is an extremely serious condition which without intervention kills the victim within minutes. It is therefore critical that the patient receives CPR within a few minutes of onset. Patients who receive bystander CPR before the arrival of EMS are two to three times more likely to survive than those who fail to get CPR.

Initiation of CPR is critical in the SCA chain of survival, which refers to a sequence of steps that should be taken in quick succession to improve the chances of survival. In the absence of bystander intervention, and with EMS arrival often taking over 5 minutes, virtually all SCA victims would die without bystander CPR and defibrillation.

Encouraging bystander action 

One of the most effective ways to encourage bystander action when witnessing a SCA, is empowering lay persons with CPR and AED training. Trained people feel more confident to intervene when they witness a medical emergency.

Boosting bystander confidence and action can be accomplished through public awareness drives and provision of AEDs.

The Avive Connect AED™ is one of three AEDs on the market today that double as a fully functional training unit, simply by swapping in a blue Training Cartridge for the red Pad Cartridge. While any AED can and should be used in an emergency, it’s powerful to train on the same device you’d be using in an emergency.

Don’t let fear prevent you from saving a life! Take action in the moment.

None of us can predict exactly how we will react during an emergency. But simply knowing about the bystander effect can help you try to overcome any hesitancy to take action that could arise in the moment.

It is a good idea to try to be mentally prepared to assist during a potential future cardiac emergency. Know that if you ever see someone collapse suddenly and become unresponsive, you will need to CALL-PUSH-SHOCK–it is important to keep this in mind at all times!

Imagine in detail how you would feel if you encountered this type of scenario. Examine any internal fears or implicit biases that are likely to emerge, and think through the set of actions you would need to take, if and when the time comes.

It may also help to be aware that robust Good Samaritan laws do exist in most states to help to absolve bystanders who offer reasonable intervention from blame in case a patient they are helping worsens or dies.

You may not feel very confident or comfortable becoming involved in an emergency situation with a complete stranger, but remember, everyday people can do extraordinary things! The person’s life could depend upon your willingness to assist. Try to remain calm and take action. If you are able to overcome any fears that arise and take action, you could save a life.

Here are a few videos on the importance of prompt bystander intervention:

Jason Grady, System Manager for Emergency Cardiac Care at Northside Hospital in Georgia, on Bystander Response:

Erick Woertink’s SCA Rescuer Story:

Dr. Dupont, Interventional Cardiologist, Northside Hospital, “Don’t Hesitate – Start CPR!”