Katz Index: a test that assesses daily activities

This test measures the degree of dependence of an individual when performing daily tasks.

We are active beings. As with other animals, humans need to carry out multiple actions in order to survive.

We need to eat, move to avoid dangers, protect ourselves from the cold... and we do all this almost without thinking, day by day and continuously. However, these actions are more complex than they seem, and although most of us have automated them, they require learning and can be lost in certain circumstances.

In many cases, due to medical or psychiatric problems (for example, an accident, an incapacitating disease or dementia), it is possible that basic and fundamental activities that we used to carry out without any problem on our own become a problem, requiring external help to carry them out. And knowing whether or not we are independent in the most basic functions can be useful to provide the help we need, or to analyze rehabilitation processes.

In order to evaluate our situation there are different indexes or scales, such as the Katz index or scale. It is about this instrument that we are going to talk about in this article.

The Katz scale/index: what is it and what is it for?

The Katz Index (sometimes also called the Katz Functional Scale) is an evaluation instrument that allows to assess the degree of physical dependence of a subject for the performance of the so-called basic activities of daily living.

With this concept we refer to the set of essential and most relevant skills for survival, self-care and self-preservation without the need to depend on external support.

It is a scale that makes it possible to evaluate the degree of dependence or independence of a subject in six basic skills: washing, dressing, using the toilet, moving around, sphincter control and feeding. These skills are organized in a hierarchical manner, ordered according to the progression that a child would carry out in his or her development.

This is relevant given that when the most fundamental activities require external support, it is common for the rest of the basic functions to also require assistance. In other words, if a person has difficulties in eating, it is likely that he/she will also have difficulties in dressing or performing any of these activities. Its use makes it possible both to assess the subject's current situation and to evaluate the progress made in rehabilitation processes.

Originally, the Functional Scale or Katz index was developed to help assess the rehabilitation carried out by people with hip fractures, although over time its function has come to be used to assess the degree of dependence of patients with various types of conditions.

It is one of the most widely used in the functional assessment of geriatric patients or in palliative care, as it allows information to be obtained on the degree of dependence of patients with various types of conditions.It is one of the most widely used in the functional assessment of geriatric patients or in palliative care, as it allows information to be obtained on the degree of help or dependence that the person needs in their daily life and to better adjust the aids provided or the rehabilitation to which they are subjected. It can be completed based on observation of the patient by professionals, or through information provided by the subject himself or by caregivers.

Items included

The Katz scale or index is an evaluation instrument that includes a total of six items to assessEach item refers to one of the basic daily living skills. Specifically, the items that are scored on this scale are as follows.

1. Washing

Bathing or washing oneself is considered a basic activity of daily life, albeit one of the most complex. A person capable of washing only one part or completely without help will be considered independent, while that person will be considered dependent if he/she needs help to wash him/herself, to get in or out of the bathtub or to wash more than one part of the body.

2. Dressing

Dressing is a complex basic activity, which requires some coordination, planning and motor skills.planning and motor skills. Independence or autonomy in this skill implies being able to pick up the necessary clothes, put them on or take them off and use elements such as buttons and zippers in order to get fully dressed. Dependence will be considered in all those cases in which the person cannot dress him/herself or can only partially dress him/herself.

3. Toilet use

A basic activity but somewhat more complex than those that follow, independent use of the toilet implies the ability to access and exit the toilet, to use it correctly, to clean oneself and to use the toilet independently.To use the toilet correctly, clean oneself and take care of one's clothes by oneself and without the need for external support. When there is dependence, help is needed to use this element or wedges or urinals are required.

4. Mobilization

Mobilization refers to the ability to move around or perform acts such as getting up, sitting or lying down in a chair or bed.. This in turn enables other basic fundamental activities to be carried out. A person with dependence in this ability will require aids to move, sit or lie down, or to use elements such as beds or chairs.

5. Continence

One of the most fundamental basic skills, continence is understood as the ability to control the processes of urination. the ability to control the processes of urination and defecation.. That is, it implies the ability to contain feces and urine and to expel them voluntarily. Habitual incontinence, whether total or partial, would be assessed as dependence in this skill.

6. Feeding

It is considered the most basic and relevant of all basic activities of daily living. The ability to feed oneself expresses the ability of the subject to move food to his or her mouth and ingest it without the need for external aids.

It is important to note that this does not include more complex processes such as cutting or spreading food with cutlery. If there is dependence in this basic skill, support will be needed to be able to feed oneself or the use of enteral or parenteral tube feeding..

Assessment of the information provided by the scale

The Katz index does not provide a numerical score and does not require complex calculations.. To assess an individual with this scale, it will be noted for each of the basic activities of daily living whether the subject is independent or dependent on external aids (including mechanical guidance, direction of action or the need for supervision).

In previous versions there was the possibility of marking a partial dependence for each of the activities, although currently only the condition of independence and dependence are considered.

Once all the items have been evaluated, the number of activities for which the person is independent is analyzed and a letter is given, which will be the total assessment of the subject's dependence/independence for these activities.

Thus we can find a person independent in all functions (A), independent in all except one (B), independent in all except bathing and one other function (C), independent in all except bathing, dressing and one other function (D), independent for all except bathing, dressing, toileting and one other function (E), independent for all except bathing, dressing, toileting, moving and one other function (F), dependent for all six functions (G) or dependent in at least two functions but not classifiable as C, D, E or F (H).