OPTimal IMAging strategy in patients suspected of non-traumatic pulmonary disease at the emergency department: chest X-ray or ultra-low-dose CT (OPTIMACT)—a randomised controlled trial chest X-ray or ultra-low-dose CT at the ED: design and rationale

Background Chest X-ray has been the standard imaging method for patients suspected of non-traumatic pulmonary disease at the emergency department (ED) for years. Recently, ultra-low-dose chest computed tomography (ULD chest CT) has been introduced, which provides substantially more detailed information on pulmonary conditions that may cause pulmonary disease, with a dose in the order of chest X-ray (0.1 vs. 0.05 mSv). The OPTimal IMAging strategy in patients suspected of non-traumatic pulmonary disease at the emergency department: chest X-ray or CT (OPTIMACT) study is a randomized trial designed to evaluate the effectiveness of replacing chest X-ray for ULD chest CT in the diagnostic work-up of patients suspected of non-traumatic pulmonary disease at the ED. Methods Two thousand four hundred patients presenting at the ED with pulmonary complaints and suspected of non-traumatic pulmonary disease will be enrolled in this multicenter, pragmatic, randomized trial. During randomly assigned periods of one calendar month, either conventional chest X-ray or ULD chest CT scan will be used as the imaging strategy. Randomization will rely on computer-generated blocks of 2 months to control for seasonal effects. Chest X-ray and ULD chest CT will be performed in a standardized way, after obtaining the clinical history and performing physical examination and initial laboratory tests. The primary outcome measure is functional health at 28 days. Secondary outcome measures are mental health, length of hospital stay, mortality within 28 days, quality-adjusted life years (QALYs) during the first 28 days, correct diagnoses at ED discharge as compared to the final post hoc diagnosis, and number of patients in follow-up because of incidental findings on chest X-ray or ULD chest CT. In an economic evaluation, we will estimate total health care costs during the first 28 days. Discussion This pragmatic trial will clarify the effects of replacing chest X-ray by ULD chest CT in daily practice, in terms of patient-related health outcomes and costs, in the diagnostic work-up of patients suspected of non-traumatic pulmonary disease at the ED. Trial registration The OPTIMACT trial is registered in the Netherlands National Trial Register under number NTR6163. The date of registration is December 6, 2016. Electronic supplementary material The online version of this article (10.1186/s41512-018-0038-1) contains supplementary material, which is available to authorized users.


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OPTIMACT PIF version 2.4, 20-2-2017 page 2 of 7 If you participate in this study, depending on the month in which you visit the Emergency Department of the AMC a chest X-ray or ultra-low-dose chest CT will be made. We would like to use your medical information for research purposes to investigate the radiologic imaging technique of choice for patients with pulmonary complaints at the Emergency Department.
The study is explained in this form. Please read this information carefully and ask the investigators for an explanation if you have any questions. You may also discuss it with your partner, friends or family. If you agree that your medical information is used for this research purpose, please fill in the subject consent form (appendix 1).

What is the purpose of the study?
The purpose of this study is to investigate for which patient population ultralow-dose chest CT had added value. It seems a logic step to replace ultralow-dose chest CT for chest X-ray because with ultra-low-dose chest CT the lungs can be evaluated in more detail. This will most likely lead to more timely diagnoses and improved patient management. There are some limitations in the use of ultra-low-dose chest CT, its availability is limited and the costs are higher. More lung nodules will be detected and patients will need additional investigations to identify the nature of the lung nodules. Only a minority of patients will benefit from these investigations. Therefore it is necessary to compare both strategies to determine whether it is effective to replace chest X-ray for ultra-low-dose CT in patients suspected of lung disease at the Emergency Department.

How is the study performed?
Each month a computer randomly selects the first imaging method of choice (chest X-ray or ultra-low-dose chest CT), for patients with complaints of the lungs at the Emergency Department who will participate in this trial.
During your visit of the Emergency Department your medical condition is assessed. Your physician does this by the evaluation of your medical complaints, information given by the nurse, physical examination and There are no advantages or disadvantages when participating. You will undergo the regular treatment and care, this will not change if you decide not to participate in this study.
Participation is not associated with additional costs. There is no compensation for participation in the OPTIMACT trial. You will not be paid for your participation in this study.

Which side effects can you expect?
There are no additional investigations in this trial and therefore no side effects can be expected. Chest X-ray and ultra-low-dose chest CT are accepted imaging methods. Both imaging techniques are radiologic techniques associated with an average radiation dose of 0.05 mSv for chest X-ray and

Are you insured when you participate?
As both Chest X-ray and ultra-low-dose chest CT are accepted diagnostic methods participation is not associated with risks., The Institutional Review Board of the AMC has waived the need for a study participants insurance.

What is done with your data and bodily material?
For this study it is necessary to collect and use your medical and personal data. All personal identifying information (e.g. name, address) will be deleted and a code will be used. This code will be used for labelling the data.

Your data
All your data will remain confidential. The investigators and research assistants are the only people who will know the code you have. The key to the code will stay with the investigators. Also in the reports about the study only this code will be used.
Some other people may access your data. This is to check whether the study is done adequate and reliable. These people are representatives of the AMC or the National Inspection of Health Care ('Inspectie voor de Gezondheidszorg').General information about this can be found in the general brochure on medical research (appendix 2).
The study results will be published. In these publications your personal information will not be identifiable.
It is mandatory that the investigator stores your data for 15 years. If you sign the consent form, you consent to your medical and personal data being General information about the registration of research can be found in the general brochure on medical research (appendix 2).

Do you want to know more?
If you have any questions, please contact the investigator, research assistent or attending physician. (You find names and contact information at the bottom of this letter.) Also during the study when you have questions or encounter a problem it is possible to ask questions to the investigator, research assistent or your own physician.
In addition, if you do not want to ask questions to the investigators before and during the study you can contact an independent physician, prof. M. Maas, radiologist. The independent physician is not involved in this study but he is knowledgeable concerning this study and your disease. If you have doubt about participation you can also ask the independent physician for advice.

Signing the subject consent form
If you decide to participate we will ask you to sign the subject consent form (appendix 1). By signing the consent form you confirm your intention to participate in this trial. You are free to withdraw at any time. The attending physician, investigator or research assistant will also sign the form confirming that he or she has informed you about the trial, has given you the information brochure and is willing to answer all your questions.

How to act in case of complains?
If you have any complaints, you can report this to the investigator or your attending physician, you may also contact the patient information desk of the AMC.