In some patient cases, physical examinations are crucial to their health and diagnosis, Dr Farrell said.
"I remember diagnosing a seriously ill diabetic by the way he smelt just as he was leaving the consult, after diagnosing him with the flu.
"If I hadn't changed my diagnosis, he may have done really badly. I think video consults may possibly lead to some misdiagnosis."
Dr Farrell said online GP conversations would be most useful in follow-up appointments.
About 2000 New Zealanders took part in the Southern Cross Primary Care Survey.
Between 17 and 24 per cent of those surveyed - depending on their age group - supported GP video consultations. Those in their 30s were most supportive, while younger respondents liked the idea least.
The survey revealed Kiwis visited their GPs, on average, 3.4 times each year. Over 50s averaged 4.3 visits annually.
GPs fees vary widely around the country - from $15 to $70.
Southern Cross Primary Care chief executive Victor Klap said online video conversations could be useful for simple health queries.
"Obviously an online video conversation with your GP would only be appropriate for certain situations.
"But there could be a number of everyday, minor health queries from regular patients that could be answered this way initially, and if further investigation was needed a face-to-face consultation could be arranged."
New Zealand Medical Association deputy chairman Mark Peterson said "tele-health" was becoming more popular with patients.
"I'm most certainly aware that some patients think this would be an excellent idea and avoid the need for face-to-face consultations.
"The most important thing is to have a pre-existing relationship with that patient so you know who you're talking to or emailing and you've got a fair idea of their medical history."
Some things such as follow-up consultations are already done by phone and email, Dr Peterson said.
"If you're a patient with high blood pressure and you've got access to a blood pressure recording machine either at home or somewhere close to you, then you can actually have your blood pressure taken and email that to your doctor."
Patients can order repeats of their medication that way, he said.
A previous survey found almost 90 per cent of patients would communicate with their doctor or a nurse via email if offered a secure website.
Ninety-five per cent of people would also use an online booking system if available.
But any consultations requiring a physical examination have to be done in person, Dr Peterson said.
He added that online video conversations could potentially save time for patients.
"It's not actually the 15 minutes you spend with the doctor, it's the waiting time and the time taken to get there.
"It may avoid you needing to take an hour or two off work and finding a carpark, which can be a real problem."
