The house-tree-person test (HTP) is a projective personality test, a type of exam in which the test taker responds to or provides ambiguous, abstract, or unstructured stimuli (often in the form of pictures or drawings). In the HTP, the test taker is asked to draw houses, trees, and persons, and these drawings provide a measure of self-perceptions and attitudes. As with other projective tests, it has flexible and subjective administration and interpretation.
The primary purpose of the HTP is to measure aspects of a person's personality through interpretation of drawings and responses to questions. It is also sometimes used as part of an assessment of brain damage or overall neurological functioning.
The HTP was developed in 1948, and updated in 1969. Tests requiring human figure drawings were already being utilized as projective personality tests. Buck believed that drawings of houses and trees could also provide relevant information about the functioning of an individual's personality.
Because it is mostly subjective, scoring and interpreting the HTP is difficult. Anyone administering the HTP must be properly trained. The test publishers provide a detailed 350-page administration and scoring manual.
The HTP can be given to anyone over the age of three. Because it requires test takers to draw pictures, it is often used with children and adolescents. It is also often used with individuals suspected of having brain damage or other neurological impairment. The test takes an average of 150 minutes to complete; it may take less time with normally functioning adults and much more time with neurologically impaired individuals.
During the first phase of the test, test takers are asked to use a crayon to draw pictures, respectively, of a house, a tree, and a person. Each drawing is done on a separate piece of paper and the test taker is asked to draw as accurately as possible. Upon completion of the drawings, test takers are asked questions about the drawings. There are a total of 60 questions that examiners can ask. Examiners can also create their own questions or ask unscripted follow-up questions. For example, with reference to the house, the test creator wrote questions such as, "Is it a happy house?" and "What is the house made of?" Regarding the tree, questions include, "About how old is that tree?" and "Is the tree alive?" Concerning the person, questions include, "Is that person happy?" and "How does that person feel?"
During the second phase of the test, test takers are asked to draw the same pictures with a pencil. The questions that follow this phase are similar to the ones in the first phase. Some examiners give only one of the two phases, choosing either a crayon, a pencil, or some other writing instrument.
One variation of test administration involves asking the individual to draw two separate persons, one of each sex. Another variation is to have test takers put all the drawings on one page.
The HTP is scored in both an objective quantitative manner and a subjective qualitative manner. The quantitative scoring scheme involves analyzing the details of drawings to arrive at a general assessment of intelligence, using a scoring method devised by the test creators. Research has shown this assessment of intelligence correlates highly with other intelligence tests such as the Wechsler adult intelligence scale (WAIS).
The primary use of the HTP, however, is related to the qualitative scoring scheme in which the test administrator subjectively analyzes the drawings and the responses to questions in a way that assesses the test taker's personality. For example, a very small house might indicate rejection of one's home life. A tree that has a slender trunk but has large expansive branches might indicate a need for satisfaction. A drawing of a person that has a lot of detail in the face might indicate a need to present oneself in an acceptable social light.
Other methods of interpretation focus on the function of various parts in each of the drawings. In the house drawing, the roof might represent one's intellectual side, the walls might represent the test taker's degree of ego strength, and the doors and windows might represent the individual's relation to the outside world. In the tree drawing, the branches might indicate the test taker's relation to the outside world and the trunk might indicate inner strength.
As with other subjectively scored personality tests, there is little support for its reliability and validity. However, there is some evidence that the HTP can differentiate people with specific types of brain damage. More specifically, it has been shown to be effective when looking at the brain damage present in schizophrenic patients.
Groth-Marnat, Gary. Handbook of Psychological Assessment. 3rd edition. New York: John Wiley and Sons, 1997.
Kline, Paul. The Handbook of Psychological Testing. New York: Routledge, 1999.
Reynolds, Cecil R. Comprehensive Clinical Psychology Volume 4: Assessment. Amsterdam: Elsevier, 1998.
Ali Fahmy, Ph.D.