R: PROscorerTools

PROscorerTools {PROscorerTools}

R Documentation

PROscorerTools

Description

Tools to score Patient-Reported Outcome (PRO), Quality of Life (QOL), and other psychometric measures and questionnaire-based instruments.

Details

Provides a set of reliable and flexible tools to score PRO, QOL, and other psychometric and psychological measures. Additionally, PROscorerTools provides the infrastructure for the scoring functions in the PROscorer package.

The scoreScale function is the workhorse of PROscorerTools, and it can be used to score most single-scale measures. For example, it can reverse code some or all items before scoring, and it can generate different types of scores (sum scores, mean scores, or scores scaled to range from 0 to 100). It and the other PROscorerTools functions can be used together to flexibly write new functions that score more complex, multi-scale measures.

The scoreScale function itself is composed of other PROscorerTools helper functions. This is an intentional feature of the PROscorerTools and PROscorer system. It represents the central design philosophy that all scoring functions should be modularly composed of a small number of well-tested, reliable helper functions. This important feature minimizes the possibility of scoring errors and other unexpected behaviors. This starts with the scoreScale function, and the benefits extend to the PROscorer functions and any other scoring function that uses scoreScale as its backbone.

Scoring procedures represent a major source of error in research studies that rely upon PRO and similar measures. These errors typically go unnoticed, hidden, and/or ignored, eroding the scientific integrity of the research and hindering progress in the numerous scientific fields that conduct studies that use these measures. A seemingly minor scoring error can compromise measurement validity and reliability, as well as make research results difficult to reproduce and unlikely to replicate. The ultimate goal of the PROscorerTools and PROscorer packages is to eliminate these serious deficiencies in PRO-based research by providing a small set of gold-standard scoring tools for PRO-like measures commonly used in research.

Overview of Functions

Main scoring workhorse:

scoreScale: Scores a single scale score from a set of items. Has flexible arguments allowing almost any type of single scale to be scored. Can be used as the primary building block of more complex scoring functions. For example, if you are writing a new function to score an instrument with 4 subscales, you can call scoreScale 4 times from within your function, once for each subscale.

Functions useful within another scoring function, or on their own:

missTally: Count the number or proportion of items missing (or non-missing) for each subject.
rerange: Linearly rescale a variable to have new min and max values of the user's choosing.
rerange100: Like rerange, but the variable is rescaled to range from 0 to 100.
revcode: Reverse code the values of an item or score.
makeItemNames: Easily make a vector of item names, e.g., c("Q1", "Q2", "Q3").
makeFakeData: Quick and dirty way to generate fake item data to test scoring functions.

Functions mainly useful only within another scoring function:

These functions are used to check the arguments supplied to custom-written scoring functions, and to perform some minimal processing of function input. AT THIS TIME, USE WITH CAUTION, IF AT ALL. Most of these (if not all) will likely undergo substantial changes in a near-future version of the package, and/or be deprecated in favor of a more streamlined system (e.g., using the assertive package).

msgWrap: Used inside of paste to help line-wrap long error and warning messages.
chk_nitems: Checks if a data frame has the correct number of items.
chkstop_nitems: Checks if a data frame has the correct number of items, and gives an error message if it does not.
chk_values: Checks if all item values in a data frame are in the expected set of possible values.
chkstop_values: Checks if all item values in a data frame are in the expected set of possible values, and gives an error message if this is not true.
get_dfItems: Given a data frame and an item index, returns a data frame containing only the items.
get_dfItemsrev: Like get_dfItems, but will also reverse code some or all of the items.

Internal Functions Used by `scoreScale`

These are internal functions used to make the scoreScale function more modular, and are used exclusively to check the arguments to that function. They will likely be of little use to others, and will probably change in a near-future version of the package, or be deprecated altogether in favor of a more streamlined system (e.g., using the assertive package). They are documented here only for development purposes. NOTE: The interface and functionality of the scoreScale function will remain stable, even if/when these functions change.

Author(s)

Maintainer: Ray Baser ray.stats@gmail.com