Transcript Slide 1
Direct Access
Dr Paul Brocklehurst
Senior Clinical Lecturer & NIHR Clinician Scientist
BDS, BSc, MDPH, PhD, FFGDP, FHEA, FDS RCS (Eng)
Learning outcomes
• Understand the evidence for:
– Comparative diagnostic test accuracy of DCPs and
GDPs when screening for caries, PD & oral cancer
– The latest Effective Practice and Organisation of Care
review on dental auxiliaries
– Current research into the productivity of using DCPs
to undertake role-substitutive tasks
Changing face of medicine
Lessons from medicine
90
85
80
CHD
Diabetes
Asthma
Usual doc
Any doc
75
70
65
60
55
50
1998
2003
2005
2007
Impact of the QOF
Overarching principles
Low variability
Nurse-led
Multi-professional clinic
Low complexity
High complexity
Nurse & doctor
Multi-professional team
High variability
Traditional model
Office of Fair Trading
• Is the UK dentistry
market working for
consumers?
– can consumers assess
and act on provided
information
– level the playing field
between providers in
the dental market
Argues for the lifting of restrictions
• “The OFT considers
these restrictions to be
unjustified and likely to
reduce patient choice and
dampen competition”
• “The OFT urges the
General Dental Council to
remove restrictions
preventing patients from
making appointments to
see dental
hygienists…and dental
therapists”
GDC’s decision
• “From today, patients
can book directly with
a dental hygienist or
dental therapist who
offers a direct access
service”
28th March 2013
“Direct access” model
Independent practice in Europe
Country
Sweden
Netherlands
Finland
Denmark
Switzerland
Italy
Norway
Year
1964
1978
1994
1996
1997
1999
2001
The NHS (PL) Regulations 2004
• To get a GDS or PDS
contract….
….you need a
Performers List
number
• DCPs can’t hold a PL
Other “buts”…
• Ionising Radiation
(Medical Exposure)
Regulations 2000 do not
recognise DCPs as
prescribers (only
operators)
• At present, GDC state
that the dentist remains
the only member of the
dental team who can
prescribe radiographs
Other “buts”…
• LA is POM which means
that under the Medicines
Act 1968 it can only be
prescribed by a qualified
prescriber – dentist
• DCPs can administer, but
only under a written,
patient-specific
prescription or under a
Patient Group Direction
(PGD) - written instruction
Other “buts”…
• Fluoride is a POM
• Fluoride can only be
prescribed under a PDG
• Written instruction without
the need for being
patient-specific
• DCPs can’t prescribe
Other “buts”…
• DCPs cannot provide
tooth whitening direct to
patients - first application
must be done by a dentist
and subsequent on
prescription. The Council
is not in a position to
change this
• Not in the practice of
dentistry, but it is a POM
So where do we go from here?
Change to a capitation system
2015
Capitation
• £50 per patient; patient list of 7,500
• Sales (income) = £375,000
£375,000
• Cost of sales =
£250,000
£150,000
• Profit =
£125,000
£225,000
What are the new incentives?
• Do the same clinical activity for less cost?
• Do less clinical activity?
• Cream-skimming
• Dumping
• Utilisation of role-substitution
Impact of impending capitation
Overarching principles
Low variability
Nurse-led
Multi-professional clinic
Low complexity
High complexity
Nurse & doctor
Multi-professional team
High variability
Population health increasing
Mean number of restored teeth
12
10
8
6
1978
1988
1998
4
2
0
16-24
25-34 35-44 45-54
Age range (years)
55+
Overarching principles
Low variability
Nurse-led
Multi-professional clinic
Low complexity
High complexity
Nurse & doctor
Multi-professional team
High variability
What is the evidence?
UoM research programme
•
•
•
•
•
•
•
•
In vitro diagnostic test accuracy study (caries)
In vivo diagnostic test accuracy study (caries)
In vitro diagnostic test accuracy study (PMD)
Feasibility study on the use of DCPs in dentistry
EPOC review on the use of DCPs in dentistry
Policy analysis of DA in the Netherlands
Systematic review of DA
Technical efficiency of role-substitutive models
in dentistry
Predicted as diseased (positive)
Diseased – True Positive
Healthy – False Positive
Sensitivity is how well the
test identifies those in the
population with the disease
[=5/6]
Specificity is how well the
test identifies those in the
population who are healthy
[=7/9]
Predicted as healthy (negative)
Truly healthy – True negative
How would you score this tooth?
1.
2.
Healthy
Suspected decay
Short 5m training exercise
102 teeth to score
Teeth sectioned – answer
All the dental team
How did dental students perform?
Dental
students
Sensitivity
.85
Specificity
.65
Were experienced dentists better?
Dental
students
GDPs
Sensitivity
.85
Specificity
.65
.85
.71
What about hygiene therapists?
Dental
students
GDPs
HTs
Sensitivity
.85
Specificity
.65
.85
.85
.71
.67
What about H-T students?
Dental
students
GDPs
HTs
HT students
Sensitivity
.85
Specificity
.65
.85
.85
.85
.71
.67
.54
And Dental Nurses…
…and the results were surprising!
Dental
students
GDPs
HTs
HT students
Dental Nurses
Sensitivity
.85
Specificity
.65
.85
.85
.85
.88
.71
.67
.54
.62
….after 5m training!
Dental nurses
Dental
students
GDPs
HTs
HT students
Dental Nurses
Sensitivity
.85
Specificity
.65
.85
.85
.85
.88
.71
.67
.54
.62
Out of the diseased teeth
examined, 88% were correctly
predicted to have disease
Out of the healthy teeth
Examined, 62% were correctly
predicted to be Healthy
Comparative efficacy in vitro
UoM research programme
•
•
•
•
•
•
•
•
In vitro diagnostic test accuracy study (caries)
In vivo diagnostic test accuracy study (caries)
In vitro diagnostic test accuracy study (PMD)
Feasibility study on the use of DCPs in dentistry
EPOC review on the use of DCPs in dentistry
Policy analysis of DA in the Netherlands
Systematic review of DA
Technical efficiency of role-substitutive models
in dentistry
Diagnostic Test Accuracy (DTA) Study
• Index Test – Dental Care Professionals (DCPs)
will perform a screen for caries and periodontal
disease.
• Reference Test – General Dental Practitioner
(GDP) independently performs an identical
screening process
Index test positive
• Any tooth with frank
cavitated lesions or
any tooth with
shadowing or opacity
consistent with
underlying dentinal
caries
Index test positive
• Probing depth of any
site on any tooth
causes the BPE
probe to disappear so
that the black band is
only partially visible
(BPE 3) or disappears
(BPE 4)
• Not about BoP
Train DCP, GDP &
Practice Manager
Identify
Practices
Recruit
patients
Pre attendance
Attendance
Check
up
Record
forms
GDP
Check
up
GDP
Formal Consent
GDP
DCP
Yes
DCP
GDP
No
Index test negative
Could DCPs be the gatekeeper?
Caries
Periodontal disease
Sensitivity
0.82
Sensitivity
0.89
Specificity
0.93
Specificity
0.84
PPV
0.82
PPV
0.83
NPV
0.93
NPV
0.91
Could DCPs be the gatekeeper?
Caries
Sensitivity
0.82
Specificity
0.93
PPV
0.82
NPV
0.93
Identifies 82% with
disease (18% FNs)
Identifies 93% who
are healthy (7% FPs)
Could DCPs be the gatekeeper?
Periodontal disease
Sensitivity
0.89
Specificity
0.84
PPV
0.83
NPV
0.91
Identifies 89% with
disease (11% FNs)
Identifies 84% who
are healthy (16% FPs)
Cumulative results - caries
1.00
0.90
0.80
0.70
0.60
0.50
Sensitivity
Specificity
0.40
0.30
0.20
0.10
0.00
0-20
21-40
41-60
61-80
81-100
101-120
121-140
141-160
Cumulative number of patients screened
161-180
181-200
Cumulative results - PD
1.00
0.90
0.80
0.70
0.60
0.50
Sensitivity
Specificity
0.40
0.30
0.20
0.10
0.00
0-20
21-40
41-60
61-80
81-100
101-120
121-140
141-160
Cumulative number of patients screened
161-180
181-200
UoM research programme
•
•
•
•
•
•
•
•
In vitro diagnostic test accuracy study (caries)
In vivo diagnostic test accuracy study (caries)
In vitro diagnostic test accuracy study (PMD)
Feasibility study on the use of DCPs in dentistry
EPOC review on the use of DCPs in dentistry
Policy analysis of DA in the Netherlands
Systematic review of DA
Technical efficiency of role-substitutive models
in dentistry
Screening for oral cancer
• Short 5m training and orientation exercise
• GDPs and DCPs across four centres [+ Netherlands]
• Diagnostic test accuracy methodology
– Index test = visual screen of clinical vignettes
– Target condition = oral cancer and PMDs
– Reference standard = histological confirmation
• Presented as summary hierarchical ROC - each point
representing the point estimate for sensitivity and
specificity for each participant (based on mean values)
The problem
• Two-sided 95.0% confidence interval for a single
proportion (sensitivity or specificity) using a z-test
approximation on an expected observed proportion of
0.90:
[n ‡ (Z2⁄m2) * p(1 – p)] = 35
• Usual procedure in DTA studies is to multiply the power
calculation by the reciprocal of the prevalence:
n * 100 / prevalence = n.
[effect size of 0.1; power of 0.8]
The problem
• Prevalence of positive lesions in general dental practice
is 4.2% (Lim et al., 2003) and would require over 700
photographs if population was modeled
• So we asked participants to screen PMD / oral cancer
from a population of malignant and benign lesions
– 35 photographs of oral malignancy or PMD (positive lesions)
– 48 (9.9%-4.2% / 4.2% * 35) photographs of benign lesions
Lim K, Moles DR, Downer MC, Speight PM. Opportunistic screening for oral cancer and
precancer in general dental practice: results of a demonstration study. Br Dent J 2003; 194: 497–502
How would you score this lesion?
5
….and how confident are you?
Results - specialists?
Specialists
Sensitivity Specificity Confidenc
e
0.85
0.74
6.62
Results - GDPs?
Specialists
GDPs
Sensitivity Specificity Confidenc
e
0.85
0.74
6.62
0.80
0.68
6.29
Results - DCPs?
Specialists
Sensitivity Specificity Confidenc
e
0.85
0.74
6.62
GDPs
0.80
0.68
6.29
DCPs
0.81
0.65
6.36
Summary ROCs
Should this surprise us? …No
• The longest running and only randomised
controlled trial used trained health care workers
and results at three, six and nine years have
demonstrated their efficacy (Sankaranarayanan
et al., 2005; Subramanian et al.,2009).
• Results from other studies using DCPs report
values of 93.3% for sensitivity and 94.3% for
specificity (Sankaranarayanan, 1997)
Brocklehurst P, Kujan O, Glenny AM, Oliver R, Sloan P, Ogden G, Shepherd S.
Screening programmes for the early detection and prevention of oral cancer.
Cochrane Database of Systematic Reviews 2010, Issue 11.
UoM research programme
•
•
•
•
•
•
•
•
In vitro diagnostic test accuracy study (caries)
In vivo diagnostic test accuracy study (caries)
In vitro diagnostic test accuracy study (PMD)
Feasibility study on the use of DCPs in dentistry
EPOC review on the use of DCPs in dentistry
Policy analysis of DA in the Netherlands
Systematic review of DA
Technical efficiency of role-substitutive models
in dentistry
Potential models - sandwich
Potential models - gatekeeper
False positives (over-referrals)
• False positives are not a problem as they
will be seen by the dentist and identified
as healthy
• From a health economic perspective, this
won’t be a problem if the numbers are
relatively small
False negatives (undetected disease)?
• False negatives should also be considered
in the context of routine attendance, where
patients would be seen again
• Dental caries is a slow growing disease in
many cohorts and so a false negative of
itself is not “life threatening”
What about undetected disease?
Broadbent JM, Thomson WM, Poulton R. Trajectory
patterns of dental caries experience in the permanent dentition to the fourth decade of life. J Dent Res 2008;87:69–72
Changes to SoP
Changes to SoP
• “Carry out a clinical
examination within
their competence”
• “Diagnose and
treatment plan within
their competence”
UoM research programme
•
•
•
•
•
•
•
•
In vitro diagnostic test accuracy study (caries)
In vivo diagnostic test accuracy study (caries)
In vitro diagnostic test accuracy study (PMD)
Feasibility study on the use of DCPs in dentistry
EPOC review on the use of DCPs in dentistry
Policy analysis of DA in the Netherlands
Systematic review of DA
Technical efficiency of role-substitutive models
in dentistry
Refreshing Galloway
• Galloway et al’s
review of DCPs for
diagnosing caries:
– Sensitivity ranged
from .71 to .94
– Specificity from .94
to .97
Refreshing Galloway
• Identified 1 cluster RCT, 2 RCTs and 1 NRCT
comparing effectiveness in FSs and ART
• Risk of bias high and GRADE very low
• No difference between GDPs and DCPs
• Paucity of high quality studies and no firm
conclusions
Dyer T, Brocklehurst P, Glenny A-M, Davies L, Tickle M, Robinson PG. Dental auxiliaries for dental
care. Cochrane Database of Systematic Reviews 2012, Issue 9. Art. No.: CD010076.
UoM research programme
•
•
•
•
•
•
•
•
In vitro diagnostic test accuracy study (caries)
In vivo diagnostic test accuracy study (caries)
In vitro diagnostic test accuracy study (PMD)
Feasibility study on the use of DCPs in dentistry
EPOC review on the use of DCPs in dentistry
Policy analysis of DA in the Netherlands
Systematic review of DA
Technical efficiency of role-substitutive models
in dentistry
Policy analysis and review of DA
• Semi-structured interviews and focus groups
were undertaken with thirty policy makers and
clinicians in the Netherlands.
• “Working relationships within integrated
practices in the Netherlands are positive, but
attitudes towards independent practice are
mixed. Good examples of collaborative working
across practices was observed”
Northcott A , Brocklehurst PR, Jerkovic K, Reindeers J-J, McDermott I, Tickle M.
Direct access: lessons learnt from the Netherlands. Br Dent J 2013 (accepted)
Policy analysis and review of DA
• 371 records identified although the extent of
experimental evidence was limited (one study)
• Majority descriptive and recorded the subjective
views of stakeholders
• “Extent of experimental evidence regarding DA
contrasts with their wide-spread use across
Europe, the US and the Southern Hemisphere”
Brocklehurst PR, Mertz B, Jerkovic K, Littlewood A, Tickle M. Direct Access to Dental
Care Professionals: an evidence synthesis. Comm Dent Oral Epidemiol (submitted)
UoM research programme
•
•
•
•
•
•
•
•
In vitro diagnostic test accuracy study (caries)
In vivo diagnostic test accuracy study (caries)
In vitro diagnostic test accuracy study (PMD)
Feasibility study on the use of DCPs in dentistry
EPOC review on the use of DCPs in dentistry
Policy analysis of DA in the Netherlands
Systematic review of DA
Technical efficiency of role-substitutive models
in dentistry
Aim
• The aim of this programme of research is to determine
the productivity (technical efficiency) of role-substitution
between GDPs and DCPs in high-street dental practices
in the NHS in the UK
• Determine whether this is influenced by the incentives
within the NHS remuneration system
• Examine barriers and enablers to the greater use of rolesubstitution in a NHS practices
Productivity
Productivity
Productivity
Workstream One
• Technical efficiency of
differing models:
– Inputs = the number of
NHS Clinical Hours worked
– Outputs = clinical activity
produced by the team
– Data envelopment analysis
– Stochastic Frontier
Modeling
• DEA is a linear model
(few assumptions)
• SFM is a parametric
model c.f. regression
• Models divided into:
– Efficient
– Inefficient
– Indifferent
Workstream Two
• Stratified purposive
sample based on
efficiency
• Semi-structured
interviews by embedded
qualitative researcher:
– practice owner
– DCP
– patient
• Methodology
– Interviews transcribed into
Nvivo
– Constant comparative
analysis
– Continue until saturation
– Thematic analysis
• Richer understanding of
using DCPs in different
team designs
Summary
• Two components of ‘efficiency’ will be examined:
– How well each practice contains costs
– How productive they are (dental services provided)
• To determine how observed efficiency depends
on the way practices have been organised
• Account for confounders:
– Patient case-mix (e.g. children)
– Geo- and demographic factors (e.g. IMD, DMFT)
Thank you