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Pro Instrument and its Types

Dr. Nancy Agens, Head,

Technical Operations, Pubrica

sales@pubrica.com

I. INTRODUCTION

Patient-Reported Outcomes (PROs) is “ a

unique health status indicator that reveals

the current and past scenarios of a ones

health condition by the patient them self,

without any other interpretation (clinician

or care giver). “Patient-Reported

Outcome” (PRO) is considered a broad

phenomenon, encompassing various

factors of perceiving and quantifying a

person’s health status, which includes

health conditions (physical and mental),

health related quality of life (HRQOL),

social well being, clinical trials, functional

status linked with the treatment taken by

the patient etc. This self- appraisal system

is high essential to identify the best

practices of a health care that is qualified

to be a good outcome leading to a patient

centered health care system.

A PRO instrument is a rating scale that

critically evaluates the health outcomes,

satisfaction scores etc in a patients

viewpoint. PRO instruments are

considered as a primordial quality

indicator for health care service, which

gives valuable insights to the policy

makers, demand market and clinical

researchers. Literature has identified

several crucial factors for development of

a PRO instrument namely

1. Study parameters should hold strong

literature support

2. Should possess a conceptual structure

3. Should be drafted based on a end-point

model

4. Study must possess ideal number of

study items

5. The model should conceal identity of

the patients

6. Reproducible at any given point of

time

7. The questionnaire should be simplified

and understandable to the patients

Information’s retrieved by the PRO

instruments are instrumental in enhancing

the relationship between the patient,

his/her family and the doctors on the

whole. Further, the universal availability

of the content is expected to bring upon

striking changes in the policies by the

regulatory authorities, drug developers,

researchers, technologists and be used for

advanced clinical trials over the time.

II. PRO INSTRUMENTS AND ITS

TYPES

Any PRO instrument is developed

adopting four essential steps as approved

by US-FDA. This includes the a.

Hypothesis derivation and drafting of the

framework b. Identifying the

literature gaps and deleting or adding the

components based on it c. critical

content validation of the instrument;

defining of the scoring indices and d.

Final draft of the SOP, evaluation of the

patient response in different perspectives,

need for translation, changes for different

geographical locations will be executed.

Generally PRO instruments are developed

based on the need, intended purpose and

the target population. The commonly

known types of PRO instruments are

Generic

Disease specific

Population specific

Dimension specific

Individualized

Summary items

Utility measures

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III. GENERIC PRO INSTRUMENT

Generic PRO instruments are used to

measure broad health aspects, illness

outcomes and are applicable for a wide

spectrum of patient groups and population

across the countries. The key benefits of

generic PRO instrument is that they are

ideally suitable to evaluate large number

of health disorders and can be used for

comparative studies among different

patient groups, treatment methods to

determine the competency of the models.

Additionally, generic PRO instrument

finds its applications in normative studies

on large population to assess the health

system, health interventions, to understand

the co-morbidities and to study the effect

of latest health care methodologies,

clinical trials etc. However, this instrument

is less sensitive as compared to other

models. Classic examples may include SF-

36, which studies the physical and mental

component of health in an 8-dimensional

scoring matrix, Psychological General

Well-Being Index (PGWBI)

IV. DISEASE SPECIFIC

This instrument aims to estimate the

patient's view of a specific disease or

disorder Specific instruments are made

developed targeting specific health

ailments. For example: Rheumatoid

Arthritis Quality of Life questionnaire

(RAQoL) developed to evaluate the patient

purview of health care and quality of life

with Rheumatoid Arthritis, The Asthma

Quality of Life Questionnaire contains 32

items yielding four dimension scores from

factors namely symptoms, activity

limitations, emotional function, and

environmental vulnerability.

V. POPULATION SPECIFIC

Population-specific instrument are

developed targeting a specific

demographic group (children or elderly

people) and geographic groups. The term

“Population specific” can be classified

based on disease condition, treatment

methods, population and geography. The

population specific PRO is a sensitive tool

is developed in precise manner to obtain

information’s in a narrowed window.

Example: The Child Health and Illness

Profile/CHIP developed for adolescents;

Cambridge Pulmonary Hypertension

Outcome Review (CAMPHOR)

VI. DIMENSION SPECIFIC

Dimension-specific instrument evaluates a

particular aspect of a person’s health. The

classic examples are physical function,

psychological wellness, personal strengths,

global health perspectives, specific role

based perceptions (house hold works, job,

finance), personal put up (appearance,

spiritual viewpoint, gratification). This

instrument is resourceful in providing

specific information as compared to the

generic or population specific PRO

instruments and they are highly competent.

It provides wide range of reliable data for

a better interpretation. The Beck

Depression Inventory contains 21 items

that effectively address symptoms of

depression.

VII. INDIVIDUALIZED PRO

INSTRUMENT

Individualized instruments enable patients

to frame their own choice of items and can

evaluate the significance of individual

items such as the health issue, other

concerns or factors that are not

predetermined by the evaluator. It

basically responds to the concerns of the

individual patient and not based on any

health standard. Therefore individualized

instruments are known to have higher

content validity. Classic example of this

PRO instrument is: The Patient Generated

Index where the respondents are asked to

list the five most important areas of their

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lives; Schedule for the Evaluation of

Individual Quality of Life (SEIQoL)

VIII. SUMMARY ITEMS

Summary item is a versatile PRO

instrument where respondents are asked to

consolidate the varied aspect of health

condition via a single item or a very small

number of items. It is less time consuming

and is used to get inputs from large sample

groups of a general population leading to

ample correlative evidences. However,

summary item restricts the specific

inferences that can be made on a specific

health disorder, which is due to its

conciseness. Example: Questions

(regarding limiting enduring illness) in

General Household Survey; the General

Household Survey for England and Wales

on chronic illness and disability.

IX. UTILITY MEASURES

Utility measures, involves choice or values

pertaining to an individual health condition

and represents it as a single index/score.

This PRO instrument evaluates the overall

strength of health status in a society and is

used for cost-utility analysis. It is

considered a generic type PRO however

uses specific numerical evaluation

methods to study health in a broad

spectrum. It is used to compare treatment

methods of different health problems and

its economic evaluation. Utility measures

are brief models and not applicable for

large number of states. Example: The

EuroQol EQ-5D contains five items

namely mobility, self-care, main activity,

pain/discomfort and anxiety/depression;

Utility measure for major, unipolar

depression (McSad)