**We set out to provide a general estimate of the time required for two different fragility fracture prevention strategies**

- BMD-first strategy: Estimates of BMD frequency were based on the 2010 guidelines from Osteoporosis Canada.
- Risk assessment-first strategy: Estimates were based on the recommendations of the Canadian Task Force on Preventive Health Care (hereafter the Task Force).

**Primary care clinician’s practice**

1200 adult patients years of age (up to 84 years old at the start)

- 600 patients are 0-49 years of age
- 300 patients are 50-64 years of age
- 300 patients are 65-84 years of age.

Half of the patients are women and half are men (see Appendix 1)

We considered screening happened until 84 years of age.

**Follow-up of the cohort of patients for 25 years**

25 years of follow-up was chosen to represent a family physician’s years of practice once stabilized, recognizing that many family physicians continue to practice for more than 25 years.

**Time needed for screening**

These times were estimated based on a convenience survey distributed in April 2023 by email and social media (see Appendix 2 for details)

* BMD -first strategy* (not recommended by the Task Force)

Ordering a BMD without risk calculation: *2.2 minutes*

Dealing with a BMD result (low-to-moderate risk or a high-risk in an individual already treated): *2.2 minutes* *(certain high-risk results might take longer but we left this duration to be conservative in our estimates – this probably underestimates the time needed for this strategy)*

Discuss +/- prescribe preventive medication (first high risk BMD): *8.2 minutes*

* Risk assessment -first strategy* (recommended by the Task Force)

Calculate FRAX, inform the patient of her risk, engage in shared decision-making (SDM) to inform if she would consider preventive medication and wants a BMD to help her decide: *6.9 minutes*

Ordering a BMD after risk calculation with FRAX: *2.2 minutes*

Discussion post-BMD +/- prescribe preventive medication: *8.2 minutes **(this discussion is probably shorter as SDM was done before the BMD, but we left this duration to be conservative in our estimates – This probably overestimates the time needed for this strategy)*

**Number of individuals screened for every 5-year period (over 25 years)**

Since we are following patients for 25 years, only patients aged 30 years and older at the beginning of the screening period would be eligible for inclusion during the last 5 years of the 25-year follow-up period (i.e., they would be between 50 to 54 during the last 5 year of the 25 years of follow-up). We used Canadian statistics to calculate the proportion of women and men in our sample patient population to generate the number of patients by 5-year age groups and sex (for those 65 to 84 years old). (See Appendix 3 for details).

Osteoporosis Canada also recommended screening women and men 50-64 years if they had risk factors. Risk factors identified in the Osteoporosis Canada 2010 recommendations included:

- Fragility fracture
- Prolonged use of glucocorticoids or other high-risk medication
- Parental hip fracture
- Vertebral fracture or osteopenia identified on radiography
- Excessive alcohol intake
- Smoking
- Low body weight (< 60 kg) or major weight loss (> 10% of body weight at age 25)
- Rheumatoid arthritis
- Other disorders strongly associated with osteoporosis

Of these, the only risk factor that can be easily estimated is the smoking rate. Estimating how many individuals within a practice would have at least one of the other above-listed risk factors (except for smoking) was not feasible. Hence, we could not estimate the patient population eligible, the number of BMD screens, nor the time needed for the BMD-first strategy for patients with risk factors 50-64 years of age (see Appendix 4).

__Repetition of screening (i.e., Number of Screens Per Person over 25 years)__

* BMD -first strategy* (not recommended by the Task Force)

Using the 2010 Osteoporosis Canada recommendations, we applied estimates for rescreening patients from 65-84 years of age over 25 years and assumed that all patients rescreened remained in the same risk category (low to moderate or high risk). Although the re-screening frequencies for moderate risk are more similar to high risk, we conservatively grouped low and moderate-risk strategies. The calculation and additional assumptions are shown in Appendix 4.

* Risk assessment -first strategy* (recommended by the Task Force)

Screening with risk assessment was calculated with a total of 2 screenings as no evidence supports the benefit to rescreen before 8 years (see Appendix 5 for details)

__Percentage of women that will consider having a BMD__ in the risk-assessment first strategy

A study by Montori et al. (2011) shows that less than half of the women (44%) would choose medication when informed of their risk with a decision aid. As the number of women who would choose a BMD is unknown, we used this same proportion as our estimate of how many women would agree to a BMD after shared decision-making (SDM).

**Estimated number of hours for varied screening options**

**The following options estimate the number of hours of clinician time over different screening strategies, over 25 years of follow-up.**

**Option 1:** **Risk assessment-first for women starting at 65 years**

300 (150 X 2): 300 X 6.9 minutes = 35 hours

132 order BMD (44%) X 2.2 minutes = 5 hours

132 discussions after BMD X 8.2 minutes = 18 hours *see note 1*

Total: 58 hours

**Option 2:** **BMD-first strategy for women starting at 65 years.**

1452 BMD ordered X 2.2 minutes = 53 hours

(850 + (602-56)) results with no medication discussions X 2.2 minutes = 51 hours* see note 2*

56 prescriptions of medication discussion X 8.2 minutes = 8 hours

Total: 112 hours * *

**Option 3:** **BMD-first strategy for women and men starting at 65 years.**

2822 BMD ordered X 2.2 minutes = 103 hours

(2102+(720-67)) results with no medication discussions X 2.2 minutes =101 hours *see note 2*

67 prescriptions of medication discussion X 8.2 minutes= 9 hours

Total: 213 hours

**Option 4: BMD-first strategy for women and men with risk factors starting at 50 years**

Unable to calculate owing to lack of estimates on population with risk factors (other than smoking). Note, this would include low, moderate and high-risk BMDs done for patients with both risk factors between 50-64 years and who would then continue to be screened at age 65+ years.

**See Appendix 3 for details on the calculation and additional assumptions**

Total BMD for women: (602 (HR) + 850(LR)) (65-84 years) = 1452

Total BMD for men: (118 (HR)+ 1252 (LR)) (65-85 years) = 1370

TOTAL BMD: 2822

*Note 1: The second discussion in the risk-assessment first strategy is probably shorter as SDM was done before the BMD, but we left this duration to be conservative in our estimates – This probably overestimates the time needed for this strategy*

*Note 2: Certain abnormal results might take longer to handle but we use this duration for all the results to be conservative in our estimates – This probably underestimates the time needed for this strategy*

For the number of screening repetitions for the risk assessment first, see the assumptions and calculations in Appendix 5

Our assumptions say that half of the patients above 50 are women and half are men

*Source: According to **statistics from 2022**, there were 14,487,356 individuals 50-85 years of age, out of which 6,864,910 were men (48.5%) and 7,282,446 women (51.5%)*

**The time needed for each step in the screening**

These times were approximated based on data from a survey distributed in April 2023 by email and social media.

90 family physicians answered the questions (see the survey questions below)

The times below are a weighted mean of the answers from the survey

- we used the upper limit of the provided times to make the calculations (ex: if the answer was 3-4 minutes we calculated with 4 minutes)
- for the answer “more than 15 minutes” we used 18 minutes
- for the last question, 11 individuals who answered that they have never used a decision aid were removed from the denominator. As such, the denominator was 79.

*Q1 : Combien de temps cela vous prend-il pour demander une ostéodensitométrie pour un(e) patient(e) (explication du test au patient, remplir le formulaire, le donner ou le transmettre au patient) *

Order a BMD:

3.3%-30sec: 1

8,9%-60 sec: 5.5

31.1%-90sec: 28

12.2%-120sec: 14.6

21.1%-180sec: 38.4

11.1%-240sec: 26.6

12.2%-300sec: 36.6

Weighted mean: 2.2 minutes

*Q2 : Combien de temps cela vous prend-il pour gérer un résultat normal d’ostéodensitométrie (lecture du résultat, consultation du dossier au besoin, classer le test)*

Normal result:

11.1%-30sec : 3.3

26.7%-60sec : 16

17.8%-90sec : 16

6.7%-120sec : 8

16.7%-180sec : 30

8.9%-240sec : 21.3

12.2%-300sec : 36.6

Weighted mean: 2.2 minutes

*Q3 : Combien de temps cela vous prend-il pour discuter avec une patiente d’un résultat anormal d’ostéodensitométrie (expliquer le résultat, expliquer les bénéfices et risques de la médication, prescrire la médication)** *

Prescribe medication:

1.1%-60sec: 0.6

1.1%-90 sec: 0.9

3.3%-120sec : 4

5.6%-180sec : 10

5.2%-240sec :12.5

18.9%-300sec : 56.7

25.6%-480sec : 122.9

23.3%-600sec : 139.8

13.3%-900sec : 119.7

2.2%-1080sec : 23.8

Weighted mean: 8.2 minutes

*Q4 : Combien de temps cela vous prend-il pour calculer le risque de fracture avec un(e) patient(e) et discuter des bénéfices et préjudices potentiels de la médication (en utilisant un outil d’aide à la décision)*

SDM:

1.3% (1/79)-30sec : 0.4

1.3% (1/79)-60sec: 0.8

7.6%- (6/79)90sec : 6.8

2.5%-(2/79)120sec : 3

10.1% (8/79)-180sec : 18.2

11.4% (9/79) – 240sec : 27.4

19% (15/79) -300sec : 57

19% (15/79) -480sec : 91.2

12.7% (10/79) -600sec : 76.2

11.4% (9/79) -900sec : 102.6

3.8% (3/79)-1080sec : 41

*As 11 participants had never used a decision aid for this purpose (the denominator used was 79)*

Weighted mean: 6.9 minutes

**Number of individuals by age**

*For ease of calculation, we considered there were no patients above 85 years old in the practice.*

**2.1 The number and proportion of women and men based on ****2022 data****.**

**Number of Women 50-64 years: 3,888,245**

Women aged 65-69 years = 1 189,864 or 35%

Women aged 70-74 years = 982,356 or 29%

Women aged 75-79 years = 734,394 or 22%

Women aged 80-84 years = 487,587 or 14%

**Men 65-84 years: 3,054,395**

Men aged 65-69 years = 1 118,232 or 37%

Men aged 70-74 years = 897,586 or 29%

Men aged 75-80 years = 647,403 or 21%

Men aged 80-84 years = 391,174 or 13%

In our sample practice, we have 300 patients 65-84 years of age (150 women and 150 men). Applying the above proportions, we would have the following number of patients in each age strata, by gender:

150 X 0.35 = **53** women aged 65-69

150 X 0.29 = **43** women aged 70-74

150 X 0.22 = **33** women aged 75-79

150 X 0.14 = **21** women aged 80-84

150 X 0.37 = **56** men aged 65-69

150 X 0.29 = **43** men aged 70-74

150 X 0.21 = **32** men aged 75-79

150 X 0.13 = **19** men aged 80-84

**Number of Screenings/- BMD-first strategy (not recommended by the Task Force)**

In the 2010 Osteoporosis Canada guideline, recommendations on screening frequency were based on a risk assessment that includes BMD (FRAX or CAROC). They recommended treating high-risk individuals (risk > 20%) and re-screening with BMD after 1 to 3 years until BMD is stabilized and then every 3-5 years. In practice, patients identified as being at high risk through BMD can be re-screened with BMD annually (e.g., annual BMD is publicly funded through OHIP in Ontario for this population). For moderate-risk (risk 10 to 20%), rescreening was recommended every 1-3 years until BMD is stable, then at an interval of 3-5 years. For individuals identified at low risk (risk < 10%), a repeat BMD screen was recommended in 3 years, then every 5-10 years if the individual remained at low risk. These recommendations use a risk threshold without any shared decision-making.

For purposes of our calculations, we used the following:

High risk = Rescreen at 2, 2, 3 then 5 years

Low to moderate risk = 2, 3, 3 then 5 years

Low risk = Rescreen at 3 then 5 years

Osteoporosis Canada also recommended screening women and men 50-64 if they had risk factors (they listed more than 10 – see the list on the first page ). Estimating how many individuals within a practice would have at least one of those risk factors (except for smoking) is not feasible.

__Individuals 65-84 years__

**Individuals 65-84** (high risk):

Repeat Intervals (years): 2, 2, then 3 years

BMD at 65-67-69-72-75-78-81-84

BMD at 70-72-74-77-80-83

BMD at 75-77-79-82-85

BMD at 80-82-84

**Individuals 65-84** (low to moderate risk):

Repeat Intervals: 2, 3, 3 then 5

BMD at 65-67-70-73-78-82

BMD at 70-72-75-78-82

BMD at 75-77-80-83

BMD at 80-82-85

Each age group will repeat itself five times during 25 years of practice (i.e., you will have 5 groups of 65-69 years that will pass through; the second group of the 70-74 years old will be the first group of the 65-69 years and so on)

High risk

65-69: 15 BMD

3 BMD (age 65-67-69) X 5 groups of this age

70-74: 7 BMD

3 BMD (age 70-72-74) X 1 (1^{st} group) +

1 BMD (age 72) X 4 (2^{nd} to 5^{th})

75-79: 10 BMD

3 BMD (age 75-77-79) X 1 (1^{st} group) +

1 BMD (age 77) X 1 (2^{nd} ) +

2 BMD (age 75-78) X 3 (3^{rd} to 5^{th} groups)

80-84: 11 BMD

3 BMD (age 80-82-84) X 1 (1^{st} group) +

2 BMD (age 82-85) X 1 (2^{nd} group ) +

2 BMD (age 80-83) X 1 (3^{rd }group) +

2 BMD (age 81-84) X 2 (4^{th} and 5^{th} groups)

Low risk

65-69: 10 BMD

2 BMD (age 65-67) X 5 groups of this age

70-74: 10 BMD

2 BMD (age 70-72) X 1 (1^{st} group) +

2 BMD (age 70-73) X 4 (2^{nd} to 5^{th})

75-79: 7 BMD

2 BMD (age 75-77) X 1 (1^{st} group) +

2 BMD (age 75-78) X 1 (2^{nd} ) +

1 BMD (age 78) X 3 (3^{rd} to 5^{th} groups)

80-84: 7 BMD

2 BMD (age 80-82) X 1 (1^{st} group) +

2 BMD (age 80-83) X 1 (2^{nd} group ) +

1 BMD (age 82) X 1 (3^{rd }group) +

1 BMD (age 82) X 2 (4^{th} and 5^{th} groups)

We used data from “Osteoporosis and related fractures in Canada: Report from the Canadian Chronic Disease Surveillance System 2020” to estimate the proportion of individuals considered high risk and thus considered treated. We consider this a conservative estimate as it likely underestimates the number of persons who will be screened if all are included.

**High risk (HR)**

Women

30.1% of women aged 65-69 years (53 X 0.301= 16 X 15 = 240)

36.2% of women aged 70-74 years (43 X 0.362= 16 X 7 = 112)

41.4% of women aged 75-79 years (33 X 0.414= 14 X 10 = 140)

45.6% of women aged 80-84 years (21 X 0.456= 10 X 11= 110)

**Total : 602 BMD **** AND 56 HR considered treated for 65+**

Men

6% of men aged 65-69 years (56 X 0.060 = 3 X 15 = 45)

7.8% of men aged 70-74 years (43 X 0.078= 3 X 7 = 21)

10% of men aged 75-79 years (32 X 0.100= 3 X 10 = 30)

12.4% of men aged 80-84 years (19 X 0.124= 2 X 11 = 22)

**Total :118 BMD **** ****AND 11 HR considered treated for 65+**

**Low or moderate risk (no data available to separate these 2 groups) – considered “normal” (LR)**

Women

69,9% of women aged 65-69 years (53 X 0.699 = 37 X 10 = 370)

63,8% of women aged 70-74 years (43 X 0.638= 27 X 10 = 270)

58,6% of women aged 75-79 years (33 X 0.586= 19 X 7 =133)

54,4% of women aged 80-84 years (21 X 0.544= 11 X 7 = 77)

**Total 850 BMD**

Men

94% of men aged 65-69 years (56 X 0.94 = 53 X 10 = 530)

92,2% of men aged 70-74 years (43 X 0.922= 40 X 10 = 400)

90% of men aged 75-79 years (32 X 0.90= 29 X 7 = 203)

87,6% of men aged 80-84 years (19 X 0.876= 17 X 7 = 119)

**Total 1252 BMD**

Total BMD for women:** (602 (HR) + 850(LR)) **(65-84 years) = 1452

Total BMD for men: (**118 (HR)+ 1252 (LR)**) (65-85 years) = 1370

TOTAL BMD: 2823

**Number of screenings – Risk assessment-first strategy (recommended by the Task Force)**

Considering that repeating before 8 years does not appear beneficial

Considering no screening before 65 years (so it could be at 66 or 67)

Considering at a certain point you will have less than 20 years to go in your practice

**Years 0-5 of your practice: number of risk assessment-first screenings**

**Women 65-69: 3**

**Women 70-74: 2**

**Women 75-79: 1.5**

**Women 80-84: 1**

**Years 6-10 of your practice (new women entering)**

**Women 65-69: 3**

**Years 11-15 of your practice (new women entering) – you only have 15 years left in your practice**

**Women 65-69: 2.5**

**Years 16-20 of your practice (new women entering) – you only have 10 years left in your practice**

**Women 65-69: 2**

**Years 21-25 of your practice (new women entering) – you only have 5 years left in your practice**

**Women 65-69: 1**

**The mean equals 2 assessments per women**