Table 1. Themes of factors influencing antibiotic prescribing from in-depth interviews with 16 prescribers in one central and one rural hospital in Laos.

Themes/sub-themes (number of participants/number of quotations)	Quotations (participant ID)
Prescribing based on their clinical judgement (15/57): 1. Patient characteristics (14/36) 2. Suspected disease/causative pathogens/ source of infection (12/17) 3. Antibiotic effects (2/2) 4. Previous antibiotic use by the patient (2/2)	“ It will be based on two things: first, on the clinical [symptoms/physical examination] of the patient. After 3–5 days of medicines, we recheck if the patient is getting better or not; our initial diagnosis is correct or not. Second, we rely on the lab [laboratory] results. If the medicines we initially provided is not the right one, then we’ll need to change medicine based on the laboratory report” (Participant 1, senior, medical ward, rural). “Before we decide to prescribe antibiotics, we need to see if it is an infection. Most of the time, we search for the source of infection by information from the family. Most importantly is physical examination, because for myself and I believe for other doctors too, we need to know the source of infection before giving any antibiotic…. Above all, we cannot forget culture every single time, at least hemoculture each time” (Participant 8, senior, intensive care unit, urban). “ If patients present with a severe condition, with any body organ being affected badly or lightly, then the medicine will be based on the class of the antibiotics, or based on how severe the body organ is affected. These should be okay.” (Participant 7, junior, medical ward, urban). “ We also have to look into the choice of medicine. For example, for a case of pneumonia, we’ll have to see which bacteria is it. We’ll choose the lowest level [narrow spectrum] of medicine for the particular age group of the child, based on which bacteria is the common cause. We will not jump to a higher level [broad spectrum] of medicines.” (Participant 3, junior, paediatric ward, urban). “ Normally in my ward, we will base on the disease of the patient. For example, appendicitis, we would give ceftri [ceftriaxone] before surgery, cloxacillin for abscess, and ampicillin for normal injury” (Participant 10, junior, surgical ward, rural). “ Those with respiratory issues, like a patient with previous pneumonia, comes to hospital because of breathing difficulty, we examine and find lung crepitation, then we’ll immediately give antibiotics because this patient has previously received antibiotics. It’s chronic” (Participant 12, junior, intensive care unit, rural).
Prescribing based on the existing resources (13/15): 1. Following laboratory results (11/13) 2. Following choice of available antibiotics in hospital (2/2)	“ Patients who are admitted in our ward must have CBC tested urgently. If it shows high white blood cells, then undoubtedly, it’s an infection and would first need antibiotics” (Participant 5, senior, medical ward, urban). “ Before prescribing antibiotic for a patient, I mainly refer to the result of white blood cells of the patient. For instance, whether the level of white blood cells is high or too low in case the patient also has fever. A second criteria is the culture result, if it comes out positive. If not based on the above-mentioned reasons, then it would be mainly based on the CBC result and the condition of the patient” (Participant 13, senior, medical ward, rural). “ The fundamental of giving antibiotics is based on the availability of medicines in the hospital” (Participant 16, junior, paediatric ward, urban).
Prescribing based on habit (7/9)	“ We rely on the prescribing app, the patient’s condition, and our habits. For instance, when the patient has respiratory distress, for example, patient has pulmonary oedema, which there’s no need for antibiotic. Sometimes it’s a habit to start antibiotic thought the patient doesn't have fever, white cell counts are not high, but antibiotics are still given. Even if we don’t give the patient antibiotics, other doctors would give antibiotics out of habit.” (Participant 9, junior, medical ward, rural). “ For cases that we give many types of medicines [combined antibiotics], is for those who have gastric perforation, for example. Like this, we need to give many medicines…. because we follow what we have been practicing” (Participant 10, junior, surgical ward, rural). “ I use 2–3 types of antibiotics in case of infections in newborns, like ampi [ampicillin] and genta [gentamicin]. If still not confident, I would add cloxa [cloxacillin] for infection of newborns of late onset at home. When we’re not sure what the bacteria is so we give them 3 types of medicine” (Participant 14, senior, paediatric ward, rural).
Prescribing due to precautionary approach (2/3)	“ We will immediately give IV for patients admitted because we don’t want them to stay in the hospital long. If patients respond to our medicine, approximately three days then they want to leave hospital and we can continue with oral medicine....... First, we avoid all the people [relatives] who come and look after the patients. Two, the bacteria within the hospital, so we want to speed up [treatment process] so they can go home fast.” (Participant 5, senior, medical ward, urban).
Following specialist recommendations (1/2)	“ We would not give antibiotics for digestive system which are not infected, like GI [gastrointestinal] bleeding. After GI tract examination and discussion with other doctors [GI specialist], antibiotic is suggested, then we’ll prescribe antibiotics” (Participant 4, senior, intensive care unit, urban).