fixedTablet {daySupply}

Fixed tablet

Description

Computes the daily dose and days' supply for prescriptions by assuming an average daily consumption of a fixed number of tablets (usually 1) per day by the patient.

Usage

fixedTablet(
  data,
  tablet = 1,
  dspd_qty,
  strength,
  id,
  serv_date,
  tot_dose_disp = NULL,
  Pt_level = FALSE
)

Arguments

data

Sample simulated data. Data may have multiple rows per person (one row per prescription fill). Required columns include: 1. ID: Patient's unique identification number 2. ServDate: Date on which each prescription was filled. 3. DSPD_QTY: Dispensed quantity: Number of tablets dispensed to patient at each prescription fill. 4. strength: Strength of the tablets dispensed.

tablet

Number of tablets assumed to be consumed by the patient per day. Default=1.

dspd_qty

Dispensed quantity: Number of the dispensed tablets to the patient at each prescription fill.

strength

Strength of the tablet dispensed in milligrams.

id

Unique patient identification number.

serv_date

Date of the prescription fill.

tot_dose_disp

Total dose dispensed: dispensed quantity x strength of the tablets dispensed for each prescription fill.

Pt_level

When TRUE, the estimated daily dose and days' supply are averaged for the patient.

Details

The fixed tablet method can be used for any medication. However, its accuracy has been shown to differ between drug classes.

Value

fixedTablet returns a dataset called "fixedTablet_result". This data set includes all the variables originally in the data, plus the following:

tot_dose_disp: Total dose dispensed at prescription fill: dispensed quantity x strength of the tablet dispensed.

fixed_1_tab_Rx_dose: Daily dose for prescription.

fixed_1_tab_Rx_DS: Days' supply for prescription.

fixed_1_tab_Pt_dose: Average daily dose for patient.

fixed_1_tab_Pt_DS: Average days' supply for patient.

Examples

#Patient collects 100 tablets of 5 mg warfarin  on January 3rd,
#and 100 tablets of 7 mg warfarin on February 1st.

#Generate a simulated dataset

library(dplyr)
n_patients <- 10
n_records <- 80
data <- data.frame(ID = rep(c(1 : n_patients), each = n_records))
data %>%
  group_by(ID) %>%
  mutate(ServDate = as.Date('2020/01/01') + abs(round(rnorm(n = 80, 700, 330))),
         DSPD_QTY = abs(round(rnorm(n = 80, 43, 28))),
         strength = abs(round(rnorm(n = 80, 4, 1))))  -> data
data <- as.data.frame(data)

#Assuming consumption of 1 tablet per day:

data_new <- fixedTablet(data, tablet = 1, Pt_level = FALSE, id = "ID",
                        dspd_qty = "DSPD_QTY", strength = "strength",
                        serv_date = "ServDate", tot_dose_disp = NULL)

#tot_dose_disp: 500mg on January 3rd and 700mg for February 1st.
#fixed_1_tab_Rx_dose: 5 mg for the prescription refill on Jan 3rd, 7 mg for prescription
#                     refill on Feb 1st.
#fixed_1_tab_Rx_DS is: For Jan 3rd:  500/5= 100 day;  For Feb 1st: 700/7= 100 days

#pt_level can be set as TRUE to get mean values for each patient
#DDD_1_Pt_dose: (5+ 7)/2 = 6 mg
#DDD_1_Pt_DS: (100+100)/2 = 100 days