Additional tables

 Observational studies included in review

Methodological quality of randomised controlled trials

Methodological quality of observational studies

Health status and health related quality of life

Quality of care in randomised controlled trials
 

Table A  Randomised controlled trials included in review (9 were in general practice setting)
 

ReferencePatient sample (setting and No of patients)Setting (No of sites)No of nurse practitioners (qualification level)* and No of doctorsMain outcomesComment
Sackett et al 1974W1Spitzer et al 1974W2Family practice: nurse practitioners, 540 families, 1529 people; doctors 1058 families, 2796 people. Subsample for patient satisfaction and health status interviews: nurse practitioners 296; doctors 521Family practice (1)2 Nurse practitioners (2); 2 doctorsHealth status; deaths; patient satisfaction; quality of care; cost effectivenessPower calculation not reported. Families were randomly allocated but had the option to swap groups (2 from doctor group and 5 from nurse practitioner group swapped.) Only 67% of patients managed entirely by nurse practitioners as nurses needed to refer to physicians for advice for a third of patients. Care over time study
Hoekelman 1975W3Well baby care: nurse practitioners 103; doctors 143Paediatric clinic; private paediatric practice (2)23 Paediatric nurse practitioners (2); 4 doctorsService use; maternal knowledge; maternal compliance; abnormality detection ratePower calculation not reported. Study complicated by comparing nurse practitioners across clinic and private practice settings. Care over time study
Burnip et al 1976W4Well child care: nurse practitioners 474; doctors 678Medical centres (2)6 Paediatric nurse practitioners (3); doctors not reportedPrescriptions; investigations; health service costs; service usePower calculation not reported. 15.7% of mothers seeing nurse practitioners wanted to change provider. Care over time study
Chambers and West 1978W5Family practice: nurse practitioners 296; doctors 572Family practice (1)1 Nurse practitioner (2); 1 doctorsPatient health status: physical, emotional, and social functionPower calculation not reported. High (37%) unexplained dropout rate and big difference between groups. Care over time study
Winter 1981W6Primary care: nurse practitioners 25; doctors 25Primary care clinic (1)5 Nurse practitioners (2); 5 doctorsPatient satisfaction with quality of carePower calculation not reported. MSc thesis. Small study. Sample: high ratio females to male providers, and preferences expressed could have been due to sex of providers
Cooper 2001W7Patients with minor injuries: nurse practitioners 102; doctors 102Emergency department (1)Nurse practitioners (4) not reported; doctors not reportedPatient satisfaction; length of consultation; No of radiographs; internal referrals; unplanned return visits; quality of careUnpublished report: pilot study for proposed randomised controlled trial¾ study too small to detect real differences
Sakr et al 1999W8Patients with recent traumatic injury: nurse practitioners 704; doctors 749Emergency department (1)Nurse practitioners (3) not reported; doctors not reportedPatient satisfaction; adequacy of careUse of 2 research registrars could have increased variation between them, such as whether radiography was needed
Kinnersley et al 2000W9Patients requesting same day appointments: nurse practitioners 652; doctors 716General practices (10)10 Nurse practitioners (2); doctors not reportedPatient satisfaction; resolution of symptoms and concerns at 2 weeks; length of consultation; prescriptions; investigations; referrals; return consultations; costsPossible selection bias. High refusal rate¾ 216 (12.3%) people refused to participate
Mundinger et al 2000W10Patients requiring primary care after emergency department visit: nurse practitioners 806; doctors 510Primary care (5)7 Nurse practitioners (1); 17 doctorsPatient satisfaction; health status; physiological measurements; healthcare utilisationStudy may be too small to detect differences for sicker patients. Recruitment bias: only 58% of those screened were recruited, and high attrition as 32.4 % randomised participants did not attend their first appointment, and those who stayed in study differed significantly at baseline. Care over time study
Shum et al 2000W11Patients requesting same day appointments: nurse practitioners 900; doctors 915General practices (5)5 Nurse practitioners (3) 19 doctorsPatient satisfaction; health status; prescriptions; length of consultation; referrals to doctor; admissions; quality of care measuresStudy did not have enough power to detect differences in rare outcomes. Some ambiguity about inclusion¾ nurses not described as nurse practitioners but given this type of training to assess and manage patients autonomously
Venning et al 2000W12Patients requesting same day appointments: nurse practitioners 651; doctors 665General practices (20)20 Nurse practitioners:(1 and 2); doctors not reportedLength of consultation; prescriptions; investigations; referrals; return consultations; patient satisfaction; health status; costsNo prior power calculation for costs. Not clear how many patients could not attend experimental sessions

*(1)=Recognised nurse practitioner programme in higher education institution leading to qualification at degree level or above; (2)=extended training in higher education institution, relevant to practice as nurse practitioner, leading to award that is less than degree level; (3)=extended training outside higher education institution relevant to enhanced practice as nurse practitioner; (4)=not possible to assign qualification.
 
 

Table B Observational studies included in review (17 were in general practice setting)
 

Study referencePatient sample (setting and No of patients)Setting

(No of sites)

No of nurse practitioners* (qualification level) and doctorsMain outcomesComment
Richards and de Castro 1973W13Children attending emergency room follow up clinic for primary care (66 nurse practitioners; 47 doctors)Primary care (1)3 Nurse practitioners (4); 1 doctorPatient satisfaction with communication; quality of careSmall study. Only one physician¾ female (sex probably significant in assessing communication)
Russo et al 1975W14113 children attending paediatric primary care outpatients (113 nurse practitioners; 113 doctors)Primary care (1)6 Nurse practitioners (3); 6 doctorsQuality of careSmall study. Patients were assessed by both providers and where researcher thought parents’ report was influenced by previous examination the patient was excluded; numbers not reported
Linn 1976W15Patients attending ambulatory care settings (273 nurse practitioners; 957doctors)Primary care (10)10 Nurse practitioners (2); doctors not reportedPatient satisfactionNo discussion of sampling or analysis. Some patients in conventional care group seen only by nurses
Komaroff et al 1976W16Ambulatory care patients with upper respiratory tract infections, genitourinary symptoms (73 nurse practitioners; 47doctors)Ambulatory care (1)1 Nurse practitioner (2); 1 doctorPatient satisfaction; resolution of symptoms; length of consultation; internal referrals; costsLikelihood of selection bias. Small sample size and power calculation not reported
De Angelis and McHugh 1977W17Children attending acute paediatric clinic (245 nurse practitioners; 211 doctors)Primary care (1)3 Nurse practitioners (3); 3 doctorsQuality of care; cost effectivenessPower calculation not reported. Costs not fully reported
Goodman and Perrin 1978W185 scenarios of mother concerned about her child’s health presented to nurse practitioners and paediatricians (19 nurse practitioners; 69 doctors)Primary care: evening phone calls (1)5 Nurse practitioners (1 and 2); 23 doctorsQuality of care; maternal satisfaction; length of callsNot clear if assessors blind. Small sample of nurse practitioner calls. Higher scores in interviewing skills correlated with higher satisfaction and longer length of call
Graham 1978W19Children presenting with new episodes of sore throat (138 nurse practitioners; 136 doctors)Primary care (1)2 Nurse practitioners (3); 3 doctorsPatient or parent satisfaction; quality of care indicators; investigations 
Hastings et al 1980W20Patients who were prison inmates (176 nurse practitioners; 136 doctors)Prison clinic (3)6 Nurse practitioners (3); doctors not reportedWorkload; quality of care; health status; patient satisfaction; mortality; test result compared to work performance of nurse practitioners; costs; return consultationsCare over time study
Salkever et al 1982W21Episodes of otitis media and sore throat treated by physicians and nurse practitioners (438 nurse practitioners; 361doctors)Primary care (1)4 Nurse practitioners (4); 4 doctorsCosts; investigations; internal referrals; consultation times; return consultations; prescriptionsComplex study involving analysis of patient encounters supplemented by small observational study to record consultation times
Powers et al 1984W22Patients attending emergency room (31 nurse practitioners; 31doctors)Emergency department (1)1 Nurse practitioner (1); 20 doctorsPatient knowledge satisfaction; compliance; resolution of problems; quality of careSmall sample size, multiple outcomes, some differences likely to be due to chance
Dunn and Higgins 1986W23Isolated North American Indian communities requiring health care (98 338 nurse practitioners; 14 935 doctors)Primary care (27)Nurse practitioners (4) not reported; doctors not reportedRange of health problems encountered; diagnostic and management patterns; prescriptionsDifferences probably related to types of patients and differences in diagnostic tendencies. Isolated communities, but in developed country: ambiguity about inclusion. Little relevance to United Kingdom. Care over time study
Salisbury and Tettersell 1988W24Patients attending general practice (210 nurse practitioners; 836 doctors)General practice (1)1 Nurse practitioner (3) 1; 1 doctorPatient satisfaction; prescriptions; referrals; presenting problems and activities of nurse practitionersNo comparative data for patient satisfaction
Campbell et al 1990W25Patients attending a family practice (136 nurse practitioners; 276 doctors)Primary care (60)Nurse practitioners (2) not reported; doctors not reportedQuality of care: provider style of delivering health careResults may be confounded by sex and case mix of sample
Rhee and Dermyer 1995W26Patients attending university emergency department (30 nurse practitioners; 30 doctors)Emergency department (1)1 Nurse practitioner (1); doctors not reportedPatient satisfactionAmbiguity over control group, unspecified number of medical students included. Strong socioeconomic selection bias as telephone survey, unable to reach 40% of prospective sample
Freij et al 1996W27Patients attending with minor injuries, injuries distal to knee and elbow (150 nurse practitioners; 150 doctors)Emergency department and minor injury unit (2)6 Nurse practitioners (3); doctors not reportedQuality of care: number of appropriate requests for radiography, number of correct interpretations of radiographsCompared senior house officers and nurse practitioners by expert review of records (records selected at two monthly intervals). Study in two different settings
Myers et al 1997W28Patients requesting urgent appointments for medical problems (500 nurse practitioners; 500 doctors)General practice

(1)

1 Nurse practitioners (1); doctors not reportedPrescriptions; referrals; admissions; return consultationsPatients self selected care, some outcomes stated were not reported (misdiagnoses and dysfunctional consultations), differences in morbidity between two groups
Bond et al 1998W29

(EROS 2)

General practice patients (305 nurse practitioners 343 doctors)General practice (4)4 Nurse practitioners (3); 28 doctorsPatient views of service; return consultationsVariability across sites
Jones et al 1998W30Simulated patients requesting primary care (9 nurse practitioners; 9 doctors)Primary care (6)3 Nurse practitioners (4); 3 doctorsFrequency of asking about urinary incontinenceSmall study. Sex bias of providers. 26% of providers realised they were seeing a simulated patient
Meek et al 1998W3120 radiographs of distal limbs for interpretation by senior house officer and nurse practitionersEmergency department (13)58 Nurse practitioners (4); 84 doctorsQuality of care: correct interpretation of radiographsComparatively few films. Not reported whether assessor was blind
Overton Brown and Anthony 1998W3250 radiographs and case histories to be interpreted and compared with consultant radiologist gold standardEmergency department (1)7 Nurse practitioners (3); 14 doctorsQuality of care: accuracy of interpretation of distal radiographsUses receiver operating characteristic method. This analysis gives graphic representation of whole spectrum of sensitivity and specificity decisions
Reveley 1998W33Patients attending for same day appointments (113 nurse practitioners; 173 doctors)General practice (1)1 Nurse practitioner (1); 7 doctorsPatient perceptions; length of consultations; prescriptions; referralsPilot study. Differences in organisation of care between providers. Interviews non-blind, subjective, fewer doctor than nurse practitioner patients, no formal assessment of satisfaction, based on convenience sample. Confounding sex bias
Byrne et al 2000W34Patients with minor injuries (57 nurse practitioners; 57 doctors)Emergency department, minor accident treatment centre (2)Nurse practitioners (4) not reported; doctors not reportedPatient satisfactionThree different settings compared. Results for the two most similar settings (emergency department and minor injury department attached to an emergency department) have been included. Doctors data gathered in June and July but nurse practitioners gathered in September to January
Cox and Jones2000W35Patients attending practice with sore throat (188 nurse practitioners; 247 doctors)General practice (1)Nurse practitioners (3) not reported; doctors not reportedPatient satisfaction; resolution of symptoms at 5 days; follow up at 1 month of patients with unresolved symptoms; use of analgesia; return consultation rates; prescriptionsPatients self selected provider. Nurse practitioners saw younger and probably less ill patients. Follow up by unblinded researcher

*(1)=Recognised nurse practitioner programme in higher education institution leading to qualification at degree level or above; (2)=extended training in higher education institution, relevant to practice as nurse practitioner, leading to award that is less than degree level; (3)=extended training outside higher education institution relevant to enhanced practice as nurse practitioner; (4)=not possible to assign qualification.
 
 

Table C Methodological quality of randomised controlled trials
 

Reference
Allocation concealment
Follow up for 80% of participants in doctor and nurse practitioner arms
Blind assessment of outcomes, or objective measures
Outcomes assessed at baseline
Reliable outcome measures
Allocation by practice or site to protect against contamination
Sackett et al 1974W1
?
Done
Done
Done
Done
Not done
Hoekelman 1975W3
?
Not done
Done
Not done
Done
Not done
Burnip et al 1976W4
?
Done
?
Not done
?
Not done
Chambers et al 1978W5
?
Not done
Done
Done
Done
Not done
Winter 1981W6
?
Not done
Done
Not done
Not done
Not done
Cooper 2001W7
Done
Not done
Done
Not done
Done
Not done
Sakr et al 1999W8
Done
Not done
Done
Not done
Done
Not done
Shum et al 2000W11
Done
Not done
Done
Not done
Done
Not done
Venning et al 2000W12
Done
Not done
Done
Done
Done
Not done
Kinnersley et al 2000W9
Done
Not done
Done
Done
Done
Not done
Mundinger et al 2000W10
?
Not done
Done
Done
Done
Done

?=Unclear or some measures only.
 
 

Table D Methodological quality of observational studies
 

Reference
Baseline characteristics reported and similar
Follow up for 80% of participants in doctor and nurse practitioner arms
Blind assessment of outcomes, or objective measures
Outcomes assessed at baseline
Reliable outcome measures
Allocation by practice or site to protect against contamination
Richards and de Castro 1973W13
Done
Not applicable
?
Not done
Not done
Not done
Russo et al 1975W14
Done
Not applicable
?
Not done
Not done
Not done
Komaroff et al 1976W16
Done
Done
?
Not done
Not done
Not done
Linn 1976W15
Not done
?
?
Not done
Not done
Not done
De Angelis and McHugh 1977W17
Done
Not applicable
?
Not done
Not done
Not done
Goodman and Perrin 1978W18
Done
Not applicable
Done
Not applicable
?
Not done
Graham 1978W19
Done
Not done
?
Not done
?
Not done
Hastings et al 1980W20
?
Done
Done
?
Not done
Not done
Salkever et al 1982W21
Done
Not applicable
Done
Not done
Done
Not done
Powers et al 1984W22
Done
Done
?
Not done
Not done
Not done
Dunn and Higgins 1986W23
Not applicable
Not applicable
?
Not done
Not done
Not done
Salisbury and Tettersell 1988W24
Done
Done
?
Not applicable
Not done
Not done
Campbell et al 1990W25
Done
Not applicable
Done
Not applicable
Not done
?
Rhee and Dermyer 1995W26
Done
Not applicable
Done
Not done
Not done
Not done
Freij et al 1996W27
?
Not done
Done
Not applicable
?
Not done
Myers et al 1997W28
Done
Done
?
Not done
?
Not done
Jones and Bunner 1998W30
Not done
Not applicable
Done
Not applicable
Not done
Not done
Meek et al 1998W31
Not done
Not applicable
Done
Not applicable
?
Not done
Bond et al 1998W29 (EROS 2)
Done
Not done
Not done
Not done
Not done
Not done
Overton-Brown and Anthony 1998W32
Done
Not applicable
Done
Not applicable
?
Not done
Reveley 1998W33
Done
?
?
Not done
Not done
Not done
Byrne et al 2000W34
Not done
Not done
Done
Not done
Done
Not done
Cox and Jones 2000W35
Done
Done
?
Not done
?
Not done

?=Unclear or some measures only.
 
 

Table E Health status and health related quality of life (randomised controlled trials)

ReferenceMeasure usedResultsConclusionComment
Sackett et al 1974W1(reports Spitzer et al 1974W2)Measures of physical function adapted from previous instruments*; health index* used for measures of emotional and social functionUnimpaired mobility, vision, hearing: nurse practitioners 255/296 (86%), doctors 458/521 (88%). Able to undertake daily activities: nurse practitioners 266/296 (90%), doctors 469/521 (90%). Freedom from bed days: nurse practitioners 255/296 (86%), doctors 453/521 (87%). Emotional function indices (1=good): nurse practitioners mean 0.583 (SD 0.187), doctors mean 0.577 (SD 0.187). Social function indices: nurse practitioners mean 0.832 (SD 0.249), doctors mean 0.839 (SD 0.274). Deaths (rate per 1000): nurse practitioners 4 (2.7), doctors 18 (6.0)Health status measurements equivalent in both groups. Physical function compared with baseline dataPower calculation not reported. Only 67% of patients received their care exclusively from nurse practitioners; of deaths reported none of patients seeing nurse practitioners were preventable
Chambers and West 1978W5WHO/ICS MCU*: health index* used for measures of emotional and social functioningPatients classified as "healthy" (χ2 P<0.01): nurse practitioners, 181/296 (61%), doctors: 284/569 (50%). Emotional function indices: nurse practitioners comparable to doctors (χ2 P<0.01). Social function indices: nurse practitioners comparable to doctors (χ2 P<0.01)Both groups of patients had similar outcomes; nurse group had better physical functionPower calculation not reported. Only one of each practitioner. Multiple outcomes
Sakr et al 1999W8Satisfaction questionnaire incorporating health status measures*Reported improved health: nurse practitioners, 373/409 (91.1%), doctors: 421/469 (89.8). Not improved as expected (P=0.41): nurse practitioners, 36/409 (8.8%), doctors: 48/469 (10.2%). Not returned to normal activities (P=0.45): nurse practitioners:74/424 (17.5%), doctors: 76/488 (15.6%)No significant difference between groupsPower calculation not reported
Kinnersley et al 2000W9Satisfaction questionnaire (CSQ) incorporating health status measuresResolution of symptoms: nurse practitioners 401/484 (82.8%), doctors 450/529 (85.1%). Resolution of concerns: nurse practitioners 221/484 (45.7%), doctors 233/529 (44.0%)No significant differences between groupsPrior power calculation
Mundinger et al 2000W10Short form SF-36*Physical summary (P=0.92): nurse practitioners mean 40.83 (SD 11.58), doctors mean 40.29 (SD 11.42). Mental summary (P=0.92): nurse practitioners mean 44.64 (SD 13.75), doctors mean 44.29 (SD 13.58). Physiological measures: no differences in physiological status for asthma (P=0.77) and diabetes patients (P=0.82). Slight difference in diastolic blood pressure 82 v 85 mm Hg (P=0.04)No significant differences in health outcomes at six months follow up. Difference in hypertension measurements only marginally of significancePrior power calculation
Shum et al 2000W11Satisfaction questionnaire (CSQ) incorporating health status measuresPatients rate condition cured or improved (P=0.906): nurse practitioners 558/672 (83%), doctors 546/661 (82.6%)Health outcomes not significantly different between practitionersPrior power calculation. Nurses had longer consultation times
Venning et al 2000W12SF-36*Physical functioning (P=0.48): nurse practitioners mean 80.78 (SD 25.11), doctors mean 82.09 (SD 24.74)No significant differences between the groups pre or post consultation in any dimensionPower calculation not reported

*Validated or referenced in paper as previously tested measure.
 
 

Table F Quality of care in randomised controlled trials
 

ReferenceMeasureResultsConclusionComment
Spitzer et al 1974W2Management of 10 indicator conditions. Use of 13 common drugsAdequate management: nurse practitioner 115/167 (69%), doctor 148/225 (66%). Adequate drug prescription: nurse practitioner 160/226 (71%), doctor 213/284 (75%)No significant differences in quality of care between nurse practitioners and doctorsPower calculation not reported. Uncertain validity of measures
Hoekelman 1975W3Physical examination of study children at age 15months by paediatricianAbnormalities undetected: nurse practitioner 6/103 (5.8%), doctor 21/143 (14.7%)Nurse practitioners missed fewer abnormalitiesPower calculation not reported. Assessor was not blinded to provider. Different settings
Cooper 2001W7Clinic referral forms completed by the reviewing doctor. Patient satisfaction questionnaire. Audit of 10% sample of notes (max score 30)Appropriate referrals (P=0.5): nurse practitioner 31/34 (91.2%), doctor 27/28 (96.4%). Satisfactory management (P=0.25): nurse practitioner 36/38 (94.7%), doctor 28/28 (100). Patient understood advice (P=0.08): nurse practitioner 79.9/85 (94.1%), doctor 65.9/78 (84.6%). Mean satisfaction scores (P=0.06): nurse practitioner (n=11) 26.45, doctor (n=9) 24.52. No missed injury: nurse practitioner 101/102 (99%), doctor 101/102 (99%)Significant differences between nurse practitioners and doctors in patients’ understanding of advice. Nurse practitioners had a higher average score on a quality audit of notesStudy too small to have detected significant differences in outcome of missed injury rates. In two cases nurse practitioners were considered to have mismanaged patients. Assessor may not have been blinded to provider. Audit of notes by researcher but measure had been tested (r=0.68, P<0.01). Study took place during last 2 months of senior house officer rotation therefore comparatively experienced
Sakr et al 1999W8A standardised record was assessed to check adequacy of care on items regarded as important in quality of care, compared to research registrar and emergency consultantNo important errors: nurse practitioner 639/704 (90.8%), doctor 745/749 (99.4%). Mechanism of injury: nurse practitioner 703/704 (99.8%); doctor 669/749 (89.3%). Accurate medical history recorded: nurse practitioner 533/704 (76%), doctor 410/749 (55%). Clinically important recording error (P=0.01): nurse practitioner 1/704 (0.15%), doctor 11/749 (1.5%). Examination: nurse practitioner 678/704 (96.3%), doctor 729/749 (97.3%). Treatment or advice: nurse practitioner 673/704 (95.6%), doctor 705/749 (94.1%). Radiograph interpretation: nurse practitioner 428/440 (97.2%), doctor 457/473 (96.6%). Follow up: nurse practitioner 684/704 (97.2%), doctor 714/749 (95.3%)Nurse practitioner care was equivalent to doctors and better in accurate recording of the medical history and interpretation of radiographs 
Kinnersley et al 2000W9Patient satisfaction questionnaire (CSQ) with additional items regarding understanding of care given by providerCause of illness: odds ratio 0.58 (95% confidence interval, 0.44 to 0.76); nurse practitioner 501/652 (81%), doctor 491/716 (72%). Relief of symptoms: 0.32 (0.24 to 0.43); nurse practitioner 548/652 (86%), doctor 467/716 (68%). Act if problem persists: 0.61 (0.41 to 0.90); nurse practitioner 584/652 (93%), doctor 604/716 (88%). How to reduce recurrence: 0.19 (0.09 to 0.38) to 1.57 (0.46 to 5.23) (range reported because odds ratios varied significantly across practices ) nurse practitioner 205/652 (34%), doctor 139/716 (21%). Patient given advice about self medication (χ2=21.123, P<0.001); nurse practitioner 193/868 (22.2%), doctor 119/871 (13.7%)

 

Patients of nurse practitioners received more information about prevention, cause, relief of symptoms, and what to do if the problem persisted than did those of doctorsOnly similar, small numbers of patients in both groups would self manage in future. Authors suggest this might be due to prescriptions validating the decision to go to see general practitioner
Shum et al 2000W11Doctor and nurse practitioner report of healthcare behaviourPatient given advice about general self management (χ2=117.766, P<0.001); nurse practitioner 709/868 (81.7%), doctor 502/871 (57.6)Patients of nurse practitioners were given more information on self management and self medicationNot validated measure

 

W1. Sackett DL, Spitzer WO, Gent M, Roberts RS. The Burlington randomized trial of the nurse practitioner: health outcomes of patients. Ann Intern Med 1974;80:137-42.

W2. Spitzer WO, Sackett DL, Sibley JC, Roberts RS, Gent M, Kergin DJ. The Burlington randomized trial of the nurse practitioner. N Engl J Med 1974;290:251-6.

W3. Hoekelman RA. What constitutes adequate well-baby care? Pediatrics 1975;55:313-26.

W4. Burnip R, Erickson R, Barr GD, Shinefield H, Schoen EJ. Well-child care by pediatric nurse practitioners in a large group practice. Am J Dis Child 1976;130:51-5.

W5. Chambers LW, West AE. The St John’s randomized trial of the family practice nurse: health outcomes of patients. Int J Epidemiol 1978;7:153-61.

W6. Winter C. Quality health care: patient assessment. 1981. MSc thesis. Long Beach, CA: California State University, 1981.

W7. Cooper M. An evaluation of the safety and effectiveness of the emergency nurse practitioner in the treatment of patients with minor injuries: a pilot study. Glasgow: Accident and Emergency, Glasgow Royal Infirmary, 2001. (Typescript.)

W8. Sakr M, Angus J, Perrin J, Nixon C, Nicholl J, Wardrope J. Care of minor injuries by emergency nurse practitioners or junior doctors: a randomised controlled trial. Lancet 1999;354:1321-6.

W9. Kinnersley P, Anderson E, Parry K, Clement J, Archard L, Turton P. Randomised controlled trial of nurse practitioner versus general practitioner care for patients requesting "same day" consultations in primary care. BMJ 2000;320:1043-8.

W10. Mundinger MO, Kane RL, Lenz ER, Totten AM, Tsai W-Y, Cleary PD. Primary care outcomes in patients treated by nurse practitioners or physicians: a randomized trial. JAMA 2000;283:59-68.

W11. Shum C, Humphreys A, Wheeler D, Cochrane MA, Skoda S, Clement S. Nurse management of patients with minor illnesses in general practice: multicentre, randomised controlled trial. BMJ 2000;320:1038-43.

W12. Venning P, Durie A, Roland M, Roberts C, Leese B. Randomised controlled trial comparing cost effectiveness of general practitioners and nurse practitioners in primary care. BMJ 2000;320:1048-53.

W13. Richards SJ, de Castro FJ. Communication with patients: a parameter in evaluating nurse practitioners. Mo Med 1973;70:719-720.

W14. Russo RM, Gururaj VJ, Bunye AS, Kim YH, Ner S. Triage abilities of nurse practitioner vs pediatrician. Am J D is Child 1975;129:673-5.

W15. Linn LS. Patient acceptance of the family nurse practitioner. Med Care 1976;14:357-64.

W16. Komaroff AL, Sawayer K, Flatley M, Browne C. Nurse practitioner management of common respiratory and genito-urinary infections using protocols. Nurs Res 1976;25:84-9.

W17. De Angelis C, McHugh M. The effectiveness of various health personnel as triage agents. J Community Health 1977;2:268-77.

W18. Goodman HC, Perrin EC. Evening telephone call management by nurse practitioners and physicians. Nurs Res 1978;27:233-7.

W19. Graham N. A quality of care assessment: pediatricians and pediatric nurse practitioners. Image 1978;10:41-8.

W20. Hastings GE, Vick L, Lee G, Sasmor L, Natiello TA, Sanders JH. Nurse practitioners in a jailhouse clinic. Med Care 1980;18:731-44.

W21. Salkever DS, Skinner E, Steinwachs DM, Katz H. Episode-based efficiency comparisons for physicians and nurse practitioners. Med Care 1982;20:143-53.

W22. Powers MJ, Jalowiec A, Reichelt PA. Nurse practitioner and physician care compared for nonurgent emergency room patients. Nurse Pract 1984;9:39-52.

W23. Dunn EV, Higgins CA. Health problems encountered by three levels of providers in a remote setting. Am J Public Health 1986;76:154-9.

W24. Salisbury CJ, Tettersell MJ. Comparison of the work of a nurse practitioner with that of a general-practitioner. J R Coll Gen Pract 1988;38:314-6.

W25. Campbell JD, Mauksch HO, Neikirk HJ, Hosokawa MC. Collaborative practice and provider styles of delivering health care. Soc Sci Med 1990;30:1359-65.

W26. Rhee KJ, Dermyer AL. Patient satisfaction with a nurse practitioner in a university emergency service. Ann Emerg Med 1995;26:130-2.

W27. Freij RM, Duffy T, Hackett D, Cunningham D, Fothergill J. Radiographic interpretation by nurse practitioners in a minor injuries unit. J Accid Emerg Med 1996;13:41-3.

W28. Myers PC, Lenci B, Sheldon MG. A nurse practitioner as the first point of contact for urgent medical problems in a general practice setting. Fam Pract 1997;14:492-7.

W29. Bond S, Cunningham W, Sargeant J, Derrick S, Beck S, Rawes G. Evaluation of nurse practitioners in general practice in Northumberland (the EROS projects 1&2). Newcastle Upon Tyne: Centre for Health Services Research, University of Newcastle Upon Tyne, 1998.

W30. Jones TV, Bunner SH. Approaches to urinary incontinence in a rural population: a comparison of physician assistants, nurse practitioners, and family physicians. J Am Board Fam Pract 1998;11:207-15.

W31. Meek S, Kendall J, Porter J, Freij R. Can accident and emergency nurse practitioners interpret radiographs? A multicentre study. J Accid Emerg Med 1998;15:105-7.

W32. Overton-Brown P, Anthony D. Towards a partnership in care: nurses’ and doctors’ interpretation of extremity trauma radiology. J Adv Nurs 1998;27:890-6.

W33. Reveley S. The role of the triage nurse practitioner in general medical practice: an analysis of the role. J Adv Nurs 1998;28:584-91.

W34. Byrne G, Richardson M, Brunsdon J, Patel A. Patient satisfaction with emergency nurse practitioners in A & E. J Clin Nurs 2000;9:83-92.

W35. Cox C. Jones M.Evaluation of the management of patients with sore throats by practice nurses and GPs. Br J Gen Pract 2000;50:872-6.