Table 4. Summary of thematic analysis results.

Domain	Theme	N (%)	Representative verbatim quotes
Factors contributing to e-prescription incidents	Incorrect calculation or entry of information	61 (24.0)	“Prescription received […] 25 mg tablet. Quantity prescribed #90. Sig: “Take 1 tablet (25 mg total) by mouth 2 times a day.” Patient misunderstood this to mean he was to take ½ tablet twice a day to give him a total daily dose of 25mg per day. Dosage should have been 1 whole tablet (25 mg) twice a day for a total daily dose of 50 mg per day. Health system recently changed their programming to include the notation of total dose. I think this will be confusing for the patients - and this is just the first example of a medication error caused by this programming change.” “Doctor sent an e-Rx and put one set of directions in the sig and another set of directions in prescriber notes.”
	Auto-population of e-prescription information	14 (5.5)	“Processing refill for patient's […] ER 10 mEq capsules. Physician e-prescribed […] CR 10 mEq tablets, with the electronic sig of: Take two capsules twice daily. We have seen this many times - with orders getting mixed up on […] capsules vs. tablets. […]- these always come up capsules since this is easier to find in their ordering systems!”
	Mismatch of e-prescription information between prescriber and pharmacy systems	18 (7.1)	“E-prescription came, but it did not match directly with pharmacy system drug file and pharmacist had to manually choose the strength. The error was not discovered by the pharmacist who entered the drug, nor by the pharmacist who checked the prescription. The patient had a proxy pick up the prescription and the patient discovered the error when it came home. If the pharmacy system matched better to the e-Prescribe Rx product and if the system made it more difficult to choose a non-equivalent product, then this error would not occur so easily.”
	Error due to interface failure	26 (10.2)	“Pharmacy received 2 E-Rx prescriptions for the same patient on same day by 2 different providers. […] was time stamped at 12:37 by provider A. […] was time stamped at 12:38 by provider B. Provider B was not onsite at this ambulatory outpatient clinic working on that day. Due to high risk medication, different providers, and timing the pharmacist looked in the EMR ([...]) for more information. There was NO record of […] prescribed that day in current or historical records. The apparent computer glitch was reported to IT.”
Potential consequences of incidents for patients	Increased likelihood of patient receiving incorrect drug therapy	79 (31.1)	“This prescription was sent over Electronically, with the wrong drug. We filled the prescription with […] 100mg it should have been […] 10mg. The doctors office just clicked on the wrong drug and sent it over electronically. The patient called the store back to let us know there was a mistake and that she had taken none of the medicine & they were bringing it back to get the correct drug.”
	Patient frustration due delayed dispensing caused by e-prescription errors	4 (1.6)	“We received a prescription for […] 250mg/5ml suspension to dispense 100ml with sig: Take by mouth 3 times daily. Take 3 times daily until gone. How much? If one teaspoon tid then does he really still just want 100ml or 10 days which would be 100ml? Had to call for dosage and quantity clarification. Of course patient is upset they have to wait and it's pharmacy's fault because “the doctor said with this new computer system this would be ready when we got here.” And of course, physician left building so they have to track him down to clarify sig.”
Potential consequences of incidents for pharmacies and pharmacy personnel	Slows down pharmacy workflow and results in additional work	11 (4.3)	“Prescriber sent rx for […] with sig of 2 puffs eight times daily resulting a phone call. Do you want 2 puffs eight times daily (maxi listed is 12 puffs in 24 hours) or do you want 2 puffs every 8 hours? […] the doctor and nurse are both gone until the end of the week, a wait time of 4 days.”
	Confusion and frustration for pharmacy personnel	37 (14.6)	“We continue to receive rx's from a particular doctor with drug selection errors, free text drugs, and drugs that the patients say they are no longer taking or do not want. We have one patient that we have received #20 rx's in July and August and they did not pick up. I am getting tired of receiving rx's that I receive no financial benefit from in filling the rx. We also are sent OTC's which we don't fill. Why should I pay for these?”
	Increased cost, audit, and insurance billing issues for pharmacy	4 (1.6)	“Prescriber denies refills citing reason “new rx to follow” and send in rx for same dose & directions as in refill request. the pharmacy pays the extra costs involved for such misuse. also, the pharmacy pays the extra costs when prescribers send duplicates & mistakenly send prescriptions for incorrect patients who use different pharmacies. prescribers tend to phone the pharmacy at that point to cancel the prescription citing unintended pharmacy.” “This issue has to deal with the cost toward each pharmacy for each e prescription sent. This is an unbelievable and unnecessary cost pharmacies have to now incorporate into their bottom lines. This goes along with lower insurance reimbursements. Thanks a lot for this extra cost that is basically taken out of our pockets.”