Context The Internet has attracted considerable attention as a means to improve
health and health care delivery, but it is not clear how prevalent Internet
use for health care really is or what impact it has on health care utilization.
Available estimates of use and impact vary widely. Without accurate estimates
of use and effects, it is difficult to focus policy discussions or design
appropriate policy activities.
Objectives To measure the extent of Internet use for health care among a representative
sample of the US population, to examine the prevalence of e-mail use for health
care, and to examine the effects that Internet and e-mail use has on users'
knowledge about health care matters and their use of the health care system.
Design, Setting, and Participants Survey conducted in December 2001 and January 2002 among a sample drawn
from a research panel of more than 60 000 US households developed and
maintained by Knowledge Networks. Responses were analyzed from 4764 individuals
aged 21 years or older who were self-reported Internet users.
Main Outcome Measures Self-reported rates in the past year of Internet and e-mail use to obtain
information related to health, contact health care professionals, and obtain
prescriptions; perceived effects of Internet and e-mail use on health care
use.
Results Approximately 40% of respondents with Internet access reported using
the Internet to look for advice or information about health or health care
in 2001. Six percent reported using e-mail to contact a physician or other
health care professional. About one third of those using the Internet for
health reported that using the Internet affected a decision about health or
their health care, but very few reported impacts on measurable health care
utilization; 94% said that Internet use had no effect on the number of physician
visits they had and 93% said it had no effect on the number of telephone contacts.
Five percent or less reported use of the Internet to obtain prescriptions
or purchase pharmaceutical products.
Conclusions Although many people use the Internet for health information, use is
not as common as is sometimes reported. Effects on actual health care utilization
are also less substantial than some have claimed. Discussions of the role
of the Internet in health care and the development of policies that might
influence this role should not presume that use of the Internet for health
information is universal or that the Internet strongly influences health care
utilization.
The Internet has been recognized for many years as an important, if
concerning, mechanism for transforming medical care.1-6 While
questions remain about its limitations,7 concerns
regarding misinformation,3,8-13 and
potential difficulties with the confidentiality of personal information,14,15 the Internet appears to have promise
as a means to disseminate information about health and health care, enhance
communication, and facilitate a wide range of interactions between patients
and the health care delivery system. These kinds of changes could produce
important improvements in health care and, ultimately, the health of the population.
Understanding the extent to which the Internet is being used for health purposes
and the effects it has on health care use would help identify the extent to
which these benefits are being realized and provide a context for fruitful
discussions of the current and future role of the Internet in health care.
Commonly cited estimates suggest that more than half15-17 and
as much as 80%18-20 of
adults with Internet access use it for health care purposes. Many of those
who use the Internet for health purposes are reported to use it frequently.
These estimates have been widely disseminated and now frequently form the
context for discussions among the media and others of the role of the Internet
in health care.21-28 However,
other, perhaps less well-publicized reports suggest much lower rates of use.14,29,30 Comparing existing
estimates can be difficult because details on aspects such as selection or
nonresponse bias are frequently not presented in the reports, many of which
appear online or as private releases rather than in peer-reviewed journals.
The wide variation in estimates of the extent of Internet use for health,
coupled with the fact that the highest estimates have been the most widely
disseminated, makes it difficult to focus discussions about the role of the
Internet in health care and develop appropriate responses. Clearer information
is needed as a foundation for future steps. This article reports results from
a survey that measures the extent of Internet use for health care among a
large, well-defined, representative sample of the US population.
We also examined the prevalence of e-mail use for health care. Previous
literature expresses both optimism and concern about the use of e-mail for
patient-physician communication.31-33 Reports
based on surveys of limited sets of patients cite widespread access to e-mail
and generally favorable attitudes toward it,34,35 but
few studies identify the prevalence of e-mail use in practice.36 Finally,
we examined the effects that Internet and e-mail use has on users' knowledge
about health care topics and their use of the health care system.
During December 2001 and January 2002, we surveyed a nationally representative
sample of the US population aged 21 years or older about their use of the
Internet and e-mail for health. We drew our sample from a research panel of
more than 60 000 households developed and maintained by Knowledge Networks
(Menlo Park, Calif), a survey research firm. To construct the panel, Knowledge
Networks used random-digit dialing to contact potential panel households,
inviting them to join the research panel. To facilitate surveying the panel
and to create an incentive for participation, they provide all households
in which an individual agrees to participate in the panel with free Internet
access via WebTV (Microsoft Inc, Redmond, Wash). Surveys of individuals from
the panel are conducted using the Internet. The ability of this research panel
to support nationally representative analyses has been studied in a number
of ways, all of which substantiate its validity. We conducted specific tests
of the validity of the survey sample used for this study, which showed that
it tracks key indicators from other major national surveys. (These analyses
are reported in an appendix to this article that is available from the authors.)
Our survey was sent to 12 878 individuals consisting of a random sample
of adults aged 21 years or older and random oversamples of individuals aged
50 or older and veterans. Responses were obtained from 8935 (69.4%) of those
surveyed. We use poststratification weights, which correct the distribution
of respondents to match the known distribution of the US population on age,
sex, race, education, region, metropolitan residence, and veteran status,
to account for the oversamples and for nonresponse.
Previous studies have typically reported rates of Internet use for health
care among respondents with Internet access. All of the members of our sample
have Internet access because all have the WebTV provided by Knowledge Networks.
Because our sample contains individuals who did not obtain Internet access
on their own, as a whole it is probably not directly comparable with samples
with Internet access analyzed in other studies. To provide comparable information,
we analyzed the subgroup of our sample who reported that they had used the
Internet before they were given WebTV. We expect this group of "Internet users"
to be comparable with those identified in other studies as Internet users.
Of the 8935 survey respondents, 4764 reported using the Internet before getting
WebTV.
The survey contained an extensive set of questions about use of the
Internet and e-mail for health care information and the perceived effects
of Internet or e-mail use on health care use. In some sections, respondents
who self-reported having any of 5 chronic conditions were asked questions
specific to their condition. The 5 conditions were heart problems (defined
as a "heart attack," coronary heart disease, angina, heart failure, or other
heart problems), cancer, diabetes, hypertension, and depression. Respondents
who indicated having more than 1 condition were randomly assigned 1 of the
conditions that they indicated for the condition-specific questions. Comparisons
of Internet and e-mail use among patients with different conditions are presented
elsewhere.37
We analyzed responses using standard tabulations. We used logistic regression
analyses to investigate the relationships between Internet and e-mail use
for health care and age, sex, annual household income, education, self-reported
health status, and residence in a Metropolitan Statistical Area. These models
exclude cases with missing data for household income and self-reported health
status. Standard errors in the regressions are adjusted for the complex survey
design. Analyses were performed using Stata (Stata Corp, College Station,
Tex). P<.05 was considered statistically significant.
Prevalence of Internet and E-mail Use for Health Information
Our analysis sample included 4764 individuals who responded to the survey
and who reported that they had used the Internet before receiving the WebTV
service. Table 1 describes the
demographic characteristics of the sample.
The survey asked 4 main questions about use of the Internet and e-mail
for health care purposes in the last year (Table 2). Approximately 40% of Internet users in our sample reported
that they used the Internet for information or advice about health or health
care during the past year. Next most common was use of e-mail or the Internet
to communicate with family or friends about health in the past year. Use of
e-mail or the Internet to communicate with a health care professional or with
other people who have similar health conditions or concerns was less common.
Among those who use the Internet for health care, use was relatively
infrequent. Thirty-one percent of respondents (who comprised 78% of those
who reported ever using the Internet for health) said they used the Internet
for health every 2 to 3 months or less. Only 9% of respondents (22% of those
who said they used the Internet for health) said they used the Internet once
a month or more. Similar frequencies were observed for use of e-mail.
We examined the relationship between the use of e-mail and use of the
Internet for health. Fifty percent of respondents said that they had used
the Internet or e-mail in at least 1 of the 4 measured ways. Of these, 42%
reported using the Internet for health information without use of e-mail.
Rates of e-mail use were notably higher among those who reported Internet
use for health. Forty-seven percent of those who reported Internet use also
reported using e-mail for 1 or more of the 3 measured purposes as opposed
to 16% of those who did not report using the Internet. Specific examination
of the association between health Internet use and e-mail communication with
physicians showed that 10% of those who reported Internet use also reported
e-mail communication with a physician as opposed to 3% of those who did not
report Internet use.
Demographics and Internet Use for Health
Table 3 reports results
from logistic regression analyses that examined the relationships between
respondent demographics and Internet and e-mail use for health. Individuals
aged 75 years or older were much less likely to report use of the Internet
for health than younger individuals. The odds of use for men were about half
of the odds for women (P<.001). We observed strong
relationships between higher education levels and higher rates of Internet
use for health but no strong relationship with income. Respondents who self-reported
worse health status were more likely to report using the Internet for health
and health care.
There were no significant demographic relationships for the rate of
making e-mail contact with a physician or other health care professional,
for which the rate of any use was low in general. Relationships between demographics
and rates of e-mail contact with family or friends were similar to those found
for Internet use for health. When we examined use of e-mail or the Internet
to contact others with similar health concerns, we found no trend toward less
use with age and a weak relationship with education. Higher-income households
were less likely to use e-mail or the Internet to contact others with similar
health concerns, and individuals reporting worse health status were more likely
to do so.
Effects of Internet Use on Health Care
We asked respondents who reported that they had ever used the Internet
or e-mail for health purposes a series of questions about the effects of Internet
or e-mail use on their knowledge about health care issues and their use of
health care. Those who indicated having heart problems, cancer, diabetes,
hypertension, or depression were asked questions about the effects of the
Internet or e-mail specific to their condition. Those who did not indicate
having 1 of these conditions were asked more general questions. These questions
were phrased so that respondents could indicate that they strongly agreed,
agreed, disagreed, or strongly disagreed that the Internet or e-mail had various
effects. Table 4 reports the percentages
of respondents who strongly agreed or agreed that use of the Internet or e-mail
had the indicated effect. Among those without any of the 5 chronic conditions,
67% said that use of the Internet improved their understanding of health care
issues, but fewer respondents said that the Internet affected more substantive
decisions or activities such as improving their ability to manage their health
care needs on their own or influencing their choice of health care professional.
We obtained similar results among those with 1 or more of the chronic conditions.
About half of these respondents indicated that use of the Internet improved
their understanding of their chronic condition, treatments for their chronic
condition, or other symptoms, conditions, or treatments, while the percentage
indicating effects on decisions about health or health care or on use of the
health care system ranged from 7% to 32%.
Two questions specifically asked about effects of Internet use on contacts
with the health care system (Table 5).
Respondents were asked about the effect of Internet or e-mail use in the last
year on the number of times they had visited or telephoned a physician or
other health care professional. In both cases, more than 90% of respondents
indicated that use of the Internet or e-mail had no effect on the number of
contacts.
Use of the Internet for Prescription Drugs
We asked respondents who self-reported that they had taken a prescription
medication in the past year several questions about their use of the Internet
for prescription drugs (Table 6).
Five percent or less said that they used the Internet to obtain prescriptions
either from their physician or from an online physician whom they had not
seen in person, purchase prescription drugs, or search for the cheapest place
to buy a prescription drug. Thirty-three percent indicated that they had used
the Internet or e-mail to learn more about a prescription drug.
Extent and Frequency of Internet Use for Health
We estimate that approximately 40% of the adult US population with Internet
access used the Internet for information or advice about health or health
care in 2001. About half of the adult US population uses the Internet at all,29 suggesting that about 20% of the entire adult population
in the United States used the Internet for health care purposes in 2001. These
numbers are substantially lower than the rates of Internet use for health
care that are often reported. Highly publicized reports have suggested that
a majority and, in some reports, even as many as 80% of US adults with Internet
access use the Internet for health care purposes.15,16,18-20 However,
our results are consistent with other, perhaps less widely publicized reports
of 35% to 37% in recent years.14,29
We also found that Internet use for health is relatively infrequent.
Seventy-eight percent of those who ever used the Internet for health care
in 2001 reported using it every 2 to 3 months or less. Only 22% of those who
ever used the Internet reported using it once a month or more. Again, our
estimates are much lower than those reported in other studies. One recent
report indicated that 59% of adults who search for health information online
do so about once a week to once a month.15 In
another report, the mean number of times per month users said they looked
for health information online was 3, and the median was 1.2.18 Our
results cannot be directly compared with these results, but our results imply
a median number of uses per month much lower than 1.2.
One plausible explanation for the differences in reported use rates
is differences in the samples. Some previous work, including the surveys that
report the highest rates of Internet use for health care,19,20 is
based on samples developed by using online recruitment. Other previous work
used telephone surveys. One possibility is that the samples used in these
studies overrepresent individuals who are particularly enthusiastic about
the Internet and who might be both more likely to use it for health information
and more willing to participate in surveys about it. Although we cannot unequivocally
rule out the existence of selection bias in our own sample, our analyses of
the sample are consistent with the view that it is representative of the population
of the United States and, thus, we do not expect that selection bias is likely
to have significantly influenced our results.
Although sample differences are a plausible explanation, we cannot provide
specific evidence about their relative importance. Other possible explanations
include differences in the wording of questions and the presentation of the
survey. We believe that our question about Internet use for health provides
a wide scope for an affirmative answer and is thus likely to capture a broad
range of use and unlikely to lead us to underestimate use, but our question
did ask about Internet use in the past year, and some other surveys are less
precise about the time frame to which questions pertain. For example, a recent
Harris Poll asked, "How often do you look for information online about health
topics—often, sometimes, hardly ever or never?"18 Differences
in the specification of the time frame could play a role in the variations
in the findings, although the comparable questions on other prominent surveys
generally appear to refer to current use patterns, which may not imply a time
frame substantially different than the past year.
It is tempting to interpret a finding that 40% of adults with Internet
access use the Internet for health care information—much lower than
common previous reports—as disappointing news for the Internet. It is
not clear to us that this is the case. Although the Internet existed a decade
ago, very few people would have used it then for health care purposes. That
the number of people using the Internet for health has grown to include 40%
of online adults could easily be viewed as a success. A useful point of comparison
is reported rates of Internet use for other activities. Results from the US
Census Bureau's Current Population Survey, a highly regarded regular survey
of the US population, suggest that about 62% of online adults use the Internet
to check news, weather, or sports information; 42% play games online; and
39% shop online.29 At the lower end, 18% report
using the Internet for banking or paying bills, 17% report accessing chat
rooms or listservs, and 9% report trading stocks online. In this context,
a utilization rate of 40% seems relatively high.
One intuitive interpretation of a utilization rate of about 40% is that
the Internet holds the most promise for a subset of the population. There
are a number of sources of health information available to interested individuals,
of which the Internet is one. Optimal results for health care delivery are
most likely to be achieved if individuals seek information from the source
that is most effective for them, and that source may not be the Internet for
everyone, not even for everyone with Internet access. It may not be reasonable
to expect that everyone with Internet access will use the Internet for health
care or that encouraging everyone with Internet access to use it for health
care information would be the best course of action. This, though, would not
mean that the Internet is not highly valuable for the subset of the population
that uses it.
Some particular challenges are highlighted by our analysis of the relationships
between demographics and Internet use for health care. In particular, we find
that individuals with less education are less likely to use the Internet for
health care. These findings parallel more general findings about the prevalence
of Internet use for any reason29 and raise
important questions about the ability of the Internet as currently structured
to provide benefits to populations that need health information and potentially
have a difficult time getting it.
Overall, these findings suggest that discussions about using the Internet
for health care should be calibrated to account for a lower prevalence and
lower frequency of use than often reported. Actions taken based on the presumption
that frequent Internet use for health is the rule rather than the exception
could be misdirected.
E-mail Use for Health Care
E-mail use in general is widespread, with nearly all online adults reporting
its use.16,29 Our results, though,
show little use of e-mail in patient-physician communications. We estimate
that 6% of US adults with Internet access used e-mail to communicate with
a health care professional in 2001, consistent with other reports suggesting
limited use in practice.16,36
Other forms of communication facilitated by e-mail should not be overlooked
in discussions of the role of online activities in health. About one quarter
of Internet users said that they used e-mail to communicate with family or
friends about health issues, which could facilitate better access to or information
about health care. Although the number was smaller, some also said that they
used e-mail or the Internet to communicate with other patients. Studies show
that information sharing can help patients in at least some situations.38-40
Effects of Using the Internet on Health Knowledge and Health Care Use
The Internet and e-mail could influence health care through a variety
of channels. One key way is by enhancing the provision of information. This
may provide intangible benefits like making patients more comfortable or confident
about their care. It may also produce more tangible effects on their use of
health care. Information gleaned from the Internet may improve patients' ability
to interact efficiently and productively with health care professionals. In
some cases, it may make them better able to care for themselves and reduce
the need to consume expensive health care resources with problems that can
be managed without additional help. Of course, it is also possible for the
Internet to provide information that would reduce the well-being of patients.
Previous work has frequently pointed out wide variations in the quality of
information available on the Internet.3,8-13 Erroneous
or poorly targeted information may lead to poor treatment choices. An overabundance
of extraneous, irrelevant, or invalid information may place new burdens on
health care professionals and detract from their ability to provide care efficiently.
Consistent with some other work,15,41 our
results suggest that Internet users can find information they consider useful
on the Internet. The majority of respondents indicated that using the Internet
or e-mail improved at least some aspect of their knowledge about health care
issues. This appears to be an encouraging sign of the ability of the Internet
and e-mail to benefit patients, although some further information would be
valuable. First, since there are not clear benchmarks for the number of users
who should be able to benefit from use, it is not clear whether the results
we observe are objectively high or low. On one hand, perhaps it is reasonable
to expect that the Internet should be able to provide at least some valuable
information to almost everyone who seeks information online. On the other
hand, perhaps many users already have a good understanding of their issue
of interest when they use the Internet. Second, although it is tempting to
infer that the well-being of users who find information they consider useful
online will have been improved, this is not necessarily true. Our study did
not have the ability to identify the objective quality of the information
found by users, nor did this study determine whether Internet use provided
information to users that they would not otherwise have obtained as opposed
to simply substituting for other information sources.
In contrast with some other reports,15 our
results suggest that the Internet is much less frequently an influence on
health care utilization, such as by affecting treatments used or making respondents
more able to manage conditions on their own. More than 90% of respondents
said that using the Internet had no effect on either physician visits or telephone
contacts.
As a whole, these results suggest that the Internet does function as
a means for informing consumers about health and health care, although there
may still be room for improvement. Effects on actual decisions are less common,
and effects on actual health care utilization are very limited. Discussions
of the role of the Internet should not presume that it is now regularly having
strong impacts on actual health care utilization.
The role of the Internet in prescription drug markets is increasingly
discussed. The Internet may be a useful way to facilitate the purchase of
prescription drugs, improving convenience for patients and saving money. It
may also undermine traditional pharmacy practices designed to maintain safety,
with patients seeking prescriptions from online physicians with limited information
on their clinical characteristics. Our results show that the practical reality
of either of these positions is currently very small. Although some respondents
report that the Internet is a source of information about prescription drugs,
almost no one indicated obtaining prescriptions or purchasing prescription
drugs online.
We found evidence of moderate rates of use of the Internet for health
care among adult Internet users, moderate effects of the Internet on the knowledge
of users, and very small effects on actual use of office visits, telephone
calls to health care professionals, and pharmaceutical purchases. Nonetheless,
the Internet clearly is an important tool with the potential to improve information
dissemination and perhaps to improve health care delivery and outcomes. Continuing
efforts to maximize the potential of this tool could have great value.
1.Kassirer JP. The next transformation in the delivery of health care.
N Engl J Med.1995;332:52-54.Google Scholar 2.Silberg WM, Lundberg GD, Musacchio RA. Assessing, controlling, and assuring the quality of medical information
on the Internet.
JAMA.1997;277:1244-1245.Google Scholar 3.Purcell GP, Wilson P, Delamothe T. The quality of health information on the Internet.
BMJ.2002;324:557-558.Google Scholar 4.Blumenthal D. Doctors in a wired world.
Milbank Q.2002;80:525-546.Google Scholar 5.Gingrich N, Magaziner I. Two old hands and the new new thing.
Health Aff (Millwood).2000;19:33-40.Google Scholar 6.National Research Council. Networking Health: Prescriptions for the Internet. Washington, DC: National Academy Press; 2000.
7.Kleinke JD. Vaporware.com: the failed promise of the health care Internet.
Health Aff (Millwood).2000;19:57-71.Google Scholar 8.Impicciatore P, Pandolfini C, Casella N, Bonati M. Reliability of health information for the public on the World Wide
Web.
BMJ.1997;314:1875-1879.Google Scholar 9.Culver JD, Gerr F, Frumkin H. Medical information on the Internet: a study of an electronic bulletin
board.
J Gen Intern Med.1997;12:466-470.Google Scholar 10.Pealer LN, Dorman SM. Evaluating health-related Web sites.
J Sch Health.1997;67:232-235.Google Scholar 11.Wyatt JC. Measuring quality and impact of the World Wide Web.
BMJ.1997;314:1879-1881.Google Scholar 12.Griffiths KM, Christiansen H. Quality of Web-based information on treatment of depression: cross
sectional survey.
BMJ.2000;321:1511-1515.Google Scholar 13.Meric F, Bernstam EV, Mirza NQ.
et al. Breast cancer on the World Wide Web: cross sectional survey of quality
of information and popularity of Websites.
BMJ.2002;324:577-581.Google Scholar 14.Pennbridge J, Moya R, Rodrigues L. Questionnaire survey of California consumers' use and rating of sources
of health care information including the Internet.
West J Med.1999;171:302-305.Google Scholar 15.Fox S, Rainie L, Horrigan J.
et al. The Online Health Care Revolution: How the Web Helps
Americans Take Better Care of Themselves. Washington, DC: Pew Internet and American Life Project; November
26, 2000.
16.Horrigan JB, Rainie L. Getting Serious Online. Washington, DC: Pew Internet and American Life Project; March 3,
2002.
17.Brodie M, Flournoy RE, Altman D.
et al. Health information, the Internet, and the digital divide.
Health Aff (Millwood).2000;19:255-265.Google Scholar 21.Reid B. Rx for the future: get an Ix, "info therapy" seeks role in health care.
Washington Post.June 25, 2002:F1.Google Scholar 22.Landro L. The informed patient: if doctors prescribe information, will patients
pay or surf the Web?
Wall Street Journal.April 25, 2002:D4.Google Scholar 24.Bly L. A network of support patients find emotional, practical advice—and
each other.
USA Today.July 14, 1999:D1.Google Scholar 25.Martin JP. A world of support; the Web is changing medicine for doctors and patients.
But is it leading to better health care?
Washington Post.August 31, 1999:Z10.Google Scholar 27.Carey B. Many Web sites can skirt privacy law, confidentiality.
Los Angeles Times.November 26, 2001:S3.Google Scholar 28.Schorow S. Web sites may net useful wellness information.
Boston Herald.January 23, 2002:Arts & Life section:45.Google Scholar 29. A Nation Online: How Americans Are Expanding Their Use of the Internet. Washington, DC: Dept of Commerce, National Telecommunications and
Information Administration and Economics and Statistics Administration; February
2002.
30.Fogel J, Albert SM, Schnabel F, Ditkoff BA, Neugut AI. Use of the Internet by women with breast cancer.
J Med Internet Res.2002;4:E9.Google Scholar 31.Borowitz SM, Wyatt JC. The origin, content, and workload of e-mail consultations.
JAMA.1998;280:1321-1324.Google Scholar 32.Eysenbach G, Diepgen TL. Responses to unsolicited patient e-mail requests for medical advice
on the World Wide Web.
JAMA.1998;280:1333-1335.Google Scholar 33.Spielberg AR. On call and online: sociohistorical, legal, and ethical implications
of e-mail for the patient-physician relationship.
JAMA.1998;280:1353-1359.Google Scholar 34.Couchman GR, Forjuoh SN, Rascoe TG. E-mail communications in family practice: what do patients expect?
J Fam Pract.2001;50:414-418.Google Scholar 35.Mandl KD, Feit S, Pena BM, Kohane IS. Growth and determinants of access in patient e-mail and Internet use.
Arch Pediatr Adolesc Med.2000;154:508-511.Google Scholar 36.Sittig DF, King S, Hazlehurst BL. A survey of patient-provider e-mail communication: what do patients
think?
Int J Med Inf.2001;61:71-80.Google Scholar 37.Wagner TH, Baker LC, Bundorf MK, Singer SJ. Use of the Internet Among the Chronically Ill. Stanford, Calif: Stanford University; 2003.
38.Spiegel D, Bloom JR, Kraemer HC, Gottheil E. Effect of psychosocial treatment on survival of patients with metastatic
breast cancer.
Lancet.1989;2:888-891.Google Scholar 39.Classen C, Butler LD, Koopman C.
et al. Supportive-expressive group therapy and distress in patients with metastatic
breast cancer: a randomized clinical intervention trial.
Arch Gen Psychiatry.2001;58:494-501.Google Scholar 40.Lorig KR, Laurent DD, Deyo RA, Marnell ME, Minor MA, Ritter PL. Can a back pain e-mail discussion group improve health status and lower
health care costs?
Arch Intern Med.2002;162:792-796.Google Scholar 41.Potts HW, Wyatt JC. Survey of doctors' experience of patients using the Internet.
J Med Internet Res.2002;4:E5.Google Scholar