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The technical term placebo is precisely applied in the specialized medical domains of pharmacology, nosology, and aetiology to denote the pharmacologically inert, dummy simulator of an "active" drug that serves as a scientific control in clinical trials designed to determine the clinical efficacy of that particular drug.
In particular, these clinical trials are conducted in order to determine whether a drug's supposedly active ingredients affect the subject through direct physiochemical processes or through mind-mediation.
- Whether the object of your faith be real or false, you will nevertheless obtain the same effects. Paracelsus (1490-1541)
Although placebos are generally characterized as pharmacologically inert substances, sham treatments, or inactive procedures, they are only inert, sham, or inactive in the particular sense that they have no known cause and effect relationship with any of the pre-designated, biochemical, physiological, behavioural, emotional and/or cognitive outcomes of the pharmacologically active and known-to-be-efficacious intervention that might have otherwise been applied.
They are, however, not inert, sham, or inactive in any other manner of speaking; and they may well, in and of themselves, generate considerable change within any given subject, at any given time, under any given circumstances.
- Actually the question of inert versus active placebo is academic, because there is no such thing as an inactive substance. For example, distilled water injections can cause hemolysis and water intoxication. Ingestion of two 5-grain [325 mg] capsules of sacchari lactis [milk sugar], QID [quater in die, "four times a day"], for 30 years, can result in a weight gain of 30 pounds, so that even sugar can hardly be considered harmless, indifferent, or inert. (Shapiro, 1968, p.675)
Applications of the term placebo
Whilst it is universally accepted that the Latin word placebo means "I shall please", the precise meaning of the English technical term placebo is not always immediately clear.
In the strictest sense, the technical term placebo denotes the inert, dummy simulator of an "active" drug that serves as a control in the clinical trials of drug efficacy, that are conducted to determine whether a drug's supposedly active ingredients affect its recipients through direct physiochemical processes or through mind-mediation.
However, some such as Gaddum (1954, p.197) have taken the position that -- by contrast with the "counterfeit objects" that are genuinely "dummy drugs" (which "cannot be distinguished from the real treatment" and are "indistinguishable in appearance, taste and smell from the real [drugs]" and, by definition, "have no effect", and "are sometimes called placebos" -- only those "counterfeit objects" that really do have some biochemical, physiological, behavioural, emotional and/or cognitive effect on a subject, and produce that effect through a psychological (rather than pharmacological) mechanism, can truly be called placebos.
- A placebo is something which is intended to act through a psychological mechanism. It is an aid to therapeutic suggestion, but the effect which it produces may be either psychological or physical. It may make the patient feel better without any obvious justification, or it may produce actual changes in such things as gastric secretion. Dummy tablets may, of course, act as placebos, but, if they do, they lose some of their value as dummy [control] tablets. They have two real functions, one of which is to distinguish pharmacological effects from the effects of suggestion, and the other is to obtain an unbiased assessment of the result of the experiment. (p.197)
In a far more general sense, the term placebo is also sometimes used to denote the pharmacologically inert, but subjectively soothing "sugar pill", electuary, or pharmaceutical syrup that a doctor might give a patient in order to gratify their need for treatment.
The term placebo may also be used pejoratively to mean a treatment or remedy that has no demonstrated efficacy whatsoever; and it is most often used to describe earlier forms of treatment to which some level of therapeutic efficacy had once been actively misattributed.
In everyday English, the word placebo is also used to denote a pharmacologically active drug, treatment or surgical procedure that has a positive, beneficial, desirable or pleasant outcome. The negative counterpart of this sort of placebo -- an active drug, treatment or procedure that has an injurious, undesirable or unpleasant outcome -- is called a nocebo.
- …a therapy may be used with or without knowledge that it is a placebo. It would include treatments given in the belief that they were not placebos, but which actually are placebos by objective evaluation. The placebo may be inert or active and may include, therefore, all medical treatment no matter how potentially specific or how administered. It may take the form of oral and parenteral medication, topical preparations, inhalants, and all mechanical, surgical, psychotherapeutic, and other therapeutic techniques. It would include a treatment that produced symptoms or side effects which were not specific for that treatment. A placebo may or may not result in a placebo effect, and the effect may be favorable or unfavorable — that is, positive or negative.
In the absence of contextual evidence -- and, in particular, in the absence of any direct knowledge of the theoretical orientation of the individual who is using the term -- it may be quite impossible to accurately and unequivocally identify its meaning in a particular case, due to the extremely wide range of different (and possibly mutually exclusive) meanings to which the term may be applied.
Uses of the term placebo
Homonymy vs. polysemy
This confusion and ambiguity within the term's application, to a large extent is due to the complex nature of the English word. For, rather than there being an extended range of linked polysemous meanings of a single term (i.e., placebo) that have multiplied, over time, from a single original source, many of the applications of the term placebo emanate from quite different sources.
Consequently, the range of different usages of the term placebo are homonymous (rather than polysemous) usages; with significantly different concepts sharing the same spelling (as with the homonyms ear, bank, sound, corn, and scale).
Origins of placebo (the simulator)
By the 8th century the Roman Catholic Church had established the final form and content of its Office of the Dead ritual.
This ceremony was designed to bring solace to the living just as much as comfort to the dead. As oart of the ritual, the celebrant would recite certain extended passages from scripture (mainly from the Psalms). At the end of each recited passage, the congregation would make a specific response (antiphon) to each recitation. The celebrant’s first recitation was Psalm 116:1-9 -- or, Psalm 114:1-9 in Septuagint version -- and the congregation’s first responding antiphon was verse 9 of that Psalm.
The Roman Catholic Church had chosen Jerome’s first (circa 384) Greek-to-Latin version of the Vulgate as the source of the celebrant’s text, rather than his third (circa 405) Hebrew-to-Latin version.
The Psalms in his first version were translated directly into Latin from the Septuagint’s Greek text. The Psalms in his third version had been translated directly from the Hebrew text of his day into Latin.
There is a significant difference in the Septuagint Psalm’s 114:9’s Latin translation, "placebo Domino in regione vivorum" ("I will please the Lord in the land of the living"), and the Hebrew Psalm's 116:9’s Latin translation, "ambulabo coram Domino in regione vivorum" ("I will walk before the Lord in the land of the living" -- which also matches the English of the King James Version) and the English version of the Islamic Zabur 116:9.
In France, it was the custom for the mourning family to distribute largesse to the congregation immediately following the Office of the Dead ritual. As a consequence, distant relatives and other unrelated parasites would attend the ceremony, simulating great anguish and grief -- in the hope of, at least, being given a meal and something to drink.
This practice was so widespread that these parasites were soon recognized as the personification of all things useless; and were considered to be archetypical simulators. Because the grief simulators' first collective act was to chant "placebo Domino in regione vivorum" they were collectively labelled (in French) as either "Placebo Singers" or "Singers of Placebo"; and they were so labelled because they sang the word "placebo", not because they were "choral placaters", using their song to please.
In the light of all of the subsequent terminological confusion it is significant that, if Jerome’s third version of the Vulgate had been selected for the ritual’s text instead of the first -- or if the Septuagint’s translators had translated an entirely different Hebrew text -- the congregation’s first response would have been "ambulabo coram Domino in regione vivorum". As a consequence, the simulators would have been "Ambulabo Singers" or "Singers of Ambulabo".
By the time of Chaucer’s Canterbury Tales (circa 1386), the disparaging English expression placebo-singer, meaning a parasite or a sycophant, was well established in the English language.
The English word placebo also denoted a sycophant, and it was this application of the word placebo that seems to have oriented those unaware of the term’s origins, over time, to the irrelevant fact that the Latin word placebo means "I shall please".
However, the first English meaning of "placebo" is simulator; and it denotes any thing that simulates any other thing (thus, A is a placebo, or simulator of B).
- …for Distinction Sake, a Deceiving by Words, is commonly called a Lye, and a Deceiving by Actions, Gestures, or Behavior, is called Simulation… Robert South (1643-1716)
South was speaking of the differences between a falsehood and an honestly mistaken statement. The difference being that, in order for the statement to be a lie, the truth must be known -- and the opposite of that truth must have been knowingly uttered -- and, from this, to the extent to which a lie involves uttering deceptive words, a simulation involves the performance of deceptive actions, deceptive gestures, or deceptive behavior.
Thus, if a simulation is genuinely false, the real truth must be known in order for some other thing (i.e., other than the truth) to be presented in its stead; otherwise, one would not know what to offer up in simulation.
Origins of placebo (the morale-booster)
Hooper’s (1811) Quincy’s Lexicon-Medicum defines placebo as "an epithet given to any medicine adapted more to please than benefit the patient".
According to Jewson, eighteenth century English medicine was gradually moving away from the patient having a considerable interaction with the physician; and, through this consultative relationship, having an equal influence on the construction of the physician’s therapeutic approach.
It was gradually moving towards that of the patient being the recipient of a far more standard form of intervention that was determined by the prevailing opinions of the medical profession of the day. Jewson characterizes this as parallel to the changes that were taking place in the manner in which medical knowledge was being produced; namely a transition all the way from "bedside medicine", through "hospital medicine", to "laboratory medicine".
From this point of view, the last vestiges of the consoling approach to treatment are to be found in the administration -- often without any sort of adequate history being taken, or any sort of appropriate physical examination being made -- of the morale-boosting and pleasing remedies, such as the "sugar pill", electuary or pharmaceutical syrup; all of which had no known pharmacodynamic action.
Those doctors who provided their patients with these sorts of morale-boosting therapies -- which, whilst having no pharmacologically active ingredients, provided reassurance and comfort -- did so either to reassure their patients whilst the vis medicatrix naturæ (i.e., "the healing power of nature") performed its normalizing task of restoring them to health, or to gratify their patients’ need for an active treatment.
- To argue with a man, and especially with a woman, that there is little the matter with them might be thought injudicious, and to advise them to return at a more convenient occasion requires more time and resolution than writing out a prescription or administering a placebo. (Steele, 1891)
By contrast, Shapiro (1968) reports that many of his respondents expressed the opinion that, in cases such as these, it was wrong to think of the medication as inert:
- If a placebo is prescribed by a physician because it is thought that it will help the patient, then it is a specific [remedy] and therefore not a placebo [at all].
An editorial in the British Medical Journal of 19 January 1952 warns that any failure of the placebo to affect the disorder for which the patient has presented for treatment may only serve to reinforce the patient's belief that they have a serious disease:
- But it is a fallacy to suppose that an inactive medicine can do no harm. If prescribed in a perfunctory way for a patient needing explanation and reassurance it may increase faith in his disease rather than in the remedy, and a doctor who gives a placebo in the wrong spirit may harm the patient. (Anon, 1952, p.150)
More than sixty years ago, Pepper noted the significant fact that "there may be a time when during the carrying out of diagnostic tests it is undesirable to give potent medicine lest it interfere with the tests and yet the patient must be encouraged by treatment" (1945, p.411). He had this to say about the application of placebos in routine medical practice:
- …there is a certain amount of skill in the choice and administration of a placebo. In the first place, it must be nothing more than what the name implies a medicine without any pharmacologic action whatever. Even a mild sedative is not a true placebo. Secondly, its name must be unknown to even the most inveterate patient who knows most drugs by name and is always quick to read the prescription. If the medicines named are familiar the type of patient who needs a placebo will promptly exclaim that this or that drug had been tried and "had not helped me" or "had upset my stomach". It is well if the drug have a Latin and polysyllabic name; it is wise if it be prescribed with some assurance and emphasis for psychotherapeutic effect. The older physicians each had his favorite placeboic prescriptions -- one chose Tincture of Condurango, another the Fluidextract [sic] of Cimificuga nigra. Certainly this latter by its Latin name might be expected to have more supratentorial action than if one merely wrote for the Black Cohosh, and Condurango would be more efficacious than sugar of milk.
Origins of placebo (the useless)
"Heroic medicine" had begun to fall from favour long before research scientists such as Robert Koch, Louis Pasteur, Frederick Hopkins and Casimir Funk demonstrated that the presence or the absence of specific agents could cause specific diseases, and long before the chemical laboratory orientation of Abraham Flexner’s 1910 Flexner Report had evolved into the evidence-based medicine of the 1970s.
As the earliest precursors of modern, scientific, conventional medicine began to emerge, medical scholars began to routinely question:
- the principles of their medical diagnosis and prognosis,
- the efficacy of their conventional medical practices,
- the correctness of their current anatomical, physiological and neurological knowledge, and
- the true scientific status of the drugs and therapies in their pharmacopoeia.
In many cases, active agents were identified within supposedly efficacious treatments; such as salicylic acid within decoctions of willow bark, which eventually led to the production of the drug aspirin.
However, it was also apparent that certain other treatments, such as the treatment of syphilis with salves made from mercury, had no efficacy whatsoever; and, regardless of the level of their acceptance within the medical profession, or the curative intentions associated with their administration, they were medically useless.
It was these sorts of useless decoctions, drugs, treatments, remedies and procedures that were given the pejorative label placebo -- the second edition of Motherby’s (1785) New Medical Dictionary defines placebo as "a common place method or medicine".
Because this usage does not appear in English -- or in any English, French, German, Italian, or Portuguese dictionary -- prior to Motherby’s 1785 edition, Shapiro (1968, pp.656-657) is certain that this pejorative use of placebo was actually coined by Motherby.
Origins of placebo (the simulator in a clinical trial)
The aim of a clinical trial is to determine what treatments, delivered in what circumstances, to which patients, in what conditions, are the most efficacious; as well to obtain objective evidence of what treatments are efficacious and specific (i.e., rather than just being efficacious), or are intentionally efficacious and specific (i.e., rather than being just intentionally efficacious or inadvertently efficacious)
In pursuit of these goals, the question “Who does what, with which, and to whom?” is central to task of identifying what are: specific effects (those for which the treatment was administered), non-specific effects (predictable "side-effects"), unintended effects (i.e., the placebo responses), or simply serendipitous effects of treatment (i.e., effects of the subject just being "in therapy").
In 1747, James Lind (1716-1794), the Naval Surgeon on HMAS Salisbury, conducted what was most likely the first-ever clinical trial when he investigated the efficacy of citrus fruit in cases of scurvy.
He randomly divided twelve scurvy patients, whose "cases were as similar as I could have them", into six pairs. Each pair was given a different remedy. He noted that the pair who had been given the citrus were so restored to health within six days of treatment that one of them returned to duty, and the other was well enough to attend the rest of the sick. Lind’s approach can still be seen in the way that the comparative efficacy of various treatments for particular sorts of cancer are determined, by examining and comparing the five year survival rates of those who have been treated with each of the different interventions.
In 1784, the French Royal Commission into the existence of animal magnetism investigated the practices of Charles d’Eslon (1739-1786); and compared the effects of his allegedly magnetized water with that of plain water.
In 1799, John Haygarth investigated the efficacy of Perkins tractors -- they were called "tractors" because they were drawn across the skin -- by comparing the results from dummy wooden tractors with a set of allegedly "active" metal tractors.
It was not until 1863 that Austin Flint (1812–1886) conducted the first-ever trial that directly compared the efficacy of a dummy simulator with that of an active treatment. This was a significant departure from the (then) customary practice of contrasting the consequences of an active treatment with what Flint described as "the natural history of [an untreated] disease".
Flint’s paper is the first time that either of the terms "placebo" or "placeboic remedy" were ever used to refer to a dummy simulator in a clinical trial.
- …to secure the moral effect of a remedy given specially for the disease, the patients were placed on the use of a placebo which consisted, in nearly all of the cases, of the tincture of quassia, very largely diluted. This was given regularly, and became well known in my wards as the placeboic remedy for rheumatism.
Origins of placebo (the benefactor)
Origins of the "placebo effect"
Origins of placebo response/reaction
Origins of the "placebo ritual"
Ambiguity of medical usage
Ambiguity of anthropological usage
- In the past, there was tendency for American authors to speak of all controls as placebos, whilst British authors tended to speak of dummy drugs, placebo therapies, and sham procedures.
- Wampold, Minami, Tierney, Baskin & Bhati (2005), p.836.
- Shapiro (1968), p.682
- Such as, for example, the word net, an openwork meshed fabric, a fishing net, cricket practice held in "the nets", a tennis net, a tennis shot that hits the net cord, etc.
- This may be due to the fact that the term placebo, in certain of its applications, is far more of an "English" word (i.e., simulator), and in others is far more of a Latin word (i.e., a "pleaser"). This phenomenon is well known across English; e.g., the term index, as in index of a book, is an established English word (because we speak of the indexes of books), but the term index, as in mathematical index, is a Latin loan-word (because we speak of mathematical indices).
- See Composition of the Book of Psalms
- http://www.hebrewoldtestament.com/B19C116.htm#V9 or Green (1997), p.502.
- The Septuagint had been translated from Hebrew into Greek, some seven centuries earlier, specifically for lodgement into the Library of Alexandria. The numbers of the Psalms are different in each of Jerome’s version, because they were numbered differently in his Septuagint and Hebrew sources. See Composition of the Book of Psalms
- * Rahlfs (1935), p.128.
- Colunga & Turrado (1965), p.553 displays both the Greek to Latin version of the Septuagint’s Psalm 114, and the Hebrew to Latin version of Psalm 116 side by side. Scholars are divided on whether the Septuagint translators were attempting to provide a more poetic translation, or whether, in using ευαρεστισω ("I shall be well pleased") instead of περιπετει ("I shall walk") they have provided a translation of an entirely different Hebrew text from the text that is accepted as the standard today. For example, the Christian scholar John Chrysostom (347 - 407) understood the Septuagint verse to mean that "those who had departed [from this life] accompanied by good deeds . . . [would] abide forever in high honor" -- and it was from this perspective that he chose to read the Septuagint as saying "I shall be pleasing in the sight of the Lord in the land of the living" (Hill, 1998, p.87). See also Popper (1945), Shapiro (1968), Lasagna (1986), Aronson (1999), and Walach (2003).
- In Chaucer’s Parson’s Tale, for example, the Parson speaks of how flatterers -- those who continuously "sing Placebo" -- are "the Devil’s Chaplains". (Perhaps Charles Darwin had Chaucer’s Parson in mind when he wrote: “What a book a Devil's Chaplain might write on the clumsy, wasteful, blundering low and horridly cruel works of nature.”)
- Chaucer’s Merchant’s Tale, which contains a character called Placebo, also includes other significantly named characters: January, the old, blind knight, with hair as white as snow; May, his beautiful, lusty, and extremely young wife (and, thus, a January-May marriage); Justinus (the noble man), his correct and thoughtful brother, who strongly advised against the marriage of January to May (which also involved a considerable transfer of money, land, and wealth to the young woman); and Placebo (the “Yes man”), his sycophantic, flattering brother, who never once raised objection to any of January’s thoughts, and actively supports January’s proposal.
- South, 1697, p.525. Samuel Johnson thought so highly of South's definition, that he used it in the entry for simulation in his Dictionary of the English Language.
- Roger Bacon’s (1214-1294) essay Of Simulation and Dissimulation expresses somewhat similar views.
- i.e., "Guérir quelquefois, soulager souvent, consoler toujours".
- Jewson (1974 & 1976).
- Jewson (1976), p.227.
- Carter (1953), p.823.
- Shapiro (1968, p.656) expresses the view that this application of the term placebo was a form of positioning: "Introduction of the word placebo to describe a class of treatments not previously specified was an important development in the history of methodology and medicine." (see Positioning (marketing))
- Steele (1891), pp.277-278.
- Shapiro (1968), p.679.
- Pepper (1945), p.411. Pepper's assertion that a placebo "must be nothing more than what the name implies" -- namely that it must be "a medicine without any pharmacologic action whatever" -- in order for it to be called a placebo, is most significant.
- N.B.: not "a common place method of medicine" as is often misquoted.
- The fact that Samuel Johnson's 1755 Dictionary of the English Language has no entry for placebo, or for placebo-singer, or for singer of placebo, strongly supports Shapiro's contention.
- Gaddum (1953):
- The first object of a therapeutic trial is to discover whether the patients who receive the treatment under investigation are cured more rapidly, more completely or more frequently, than they would have been without it. (p.195)
- Chambless & Hollon (1998)
- Lohr, Olatunji, Parker & DeMaio (2005).
- Perlman (2001). In discussing the "unrecognized serendipitous effects of being in therapy", Perlman (p.283) suggests the following as examples: the "organizing effects of the therapeutic structure", "inadvertent role modeling", "outside knowledge of the therapist", "chance remarks or encounters", and "the influence of auxiliary personnel" ("this category includes doormen, receptionists, cashiers, secretaries, security guards, janitors, and child care attendants", p.287). Gaddum (1954) also recognizes that "changes in the incidence or severity of diseases in a hospital may be due to changes in the diet or changes in the nurses, which happen to coincide with the introduction of a new treatment" (pp.195-196).
- According to Lind’s 1753 Treatise on the Scurvy in Three Parts Containing an Inquiry into the Nature, Causes, and Cure of the Disease, Together with a Critical and Chronological View of what has been Published of the Subject, the remedies were: (a) one quart of cider per day, (b) twenty-five drops of elixir vitriol (aromatic sulphuric acid) three times a day, (c) two spoonfuls of vinegar three times a day, (d) a course of sea-water (half a pint every day), (e) two oranges and one lemon each day, and (f) an electuary (Dunn, 1997, p.F65). According to Gaddum (1954, p.196) the electuary had been recommended to Lind by a hospital surgeon, and it contained garlic, mustard, balsam of Peru, and myrrh.
- Dunn (1997), p.F65.
- It did not examine the practices of Franz Mesmer. It examined the significantly different practices of his associate Charles d’Eslon.
- Gauld (1992), p.28.
- Green, (2002).
- See Austin Flint murmur
- Flint (1863), p.18.
- Flint (1863), p.21. Flint treated 13 hospital inmates that had rheumatic fever; 11 were "acute", and 2 were "sub-acute". He then compared the results of his dummy "placeboic remedy" with that of the active treatment’s already well-understood results (Flint had previously tested, and reported on, the active treatment’s efficacy). There was no significant difference between the results of the active treatment and his "placeboic remedy" in 12 of the cases in terms of disease duration, duration of convalescence, number of joints affected, and emergence of complications (pp.32-34). In the thirteenth case, Flint expressed some doubt as to whether the particular complications that had emerged -- namely, pericarditis, endocarditis, and pneumonia -- would have been prevented if that subject had been immediately given the "active treatment" (p.36).
- Anon, "The Bottle of Medicine" [Editorial], British Medical Journal, No.4750, (19 January 1952), pp.149-150.
- Aronson, J., "When I use a word . . . Please, please me", British Medical Journal, Vol.318, No.7185, (13 March 1999), p.716.
- Bacon, R., Of Simulation and Dissimulation, 1597.
- Bernheim, H. (trans. by Herter C.A. from Second, revised French Edition of 1887), Suggestive Therapeutics: A Treatise on the Nature and Uses of Hypnotism, G.P. Putnam's Sons, (New York), 1889.
- Carter, A.B., "The Placebo: Its Use and Abuse", The Lancet, Vol.262, No.6790, (17 October 1953), p.823.
- Chambless, D.L. & Hollon, S.D., "Defining Empirically Supported Therapies", Journal of Consulting and Clinical Psychology, Vol.66, No.1, (February 1998), pp.7-18.
- Colunga, A. & Turrado, L. (eds.), Biblia sacra iuxta Vulgatam Clementinam nova editio Logis partitionibus aliisque subsidiis ornata a A. Colunga et L. Turrado, Biblioteca de autores cristianos, (Madrid), 1965.
- Ernst, E. & Resch, K.L., "Concept of True and Perceived Placebo Effects", British Medical Journal, (26 August 1995), Vol.311, No.7004, pp.551-553.
- Flexner, A., Medical Education in the United States and Canada: A Report to the Carnegie Foundation for the Advancement of Teaching (Bulletin Number Four), The Merrymont Press, (Boston), 1910. 
- Flint, A., "A Contribution Toward the Natural History of Articular Rheumatism, Consisting of a Report of Thirteen Cases Treated Solely with Palliative Measures", American Journal of Medical Science, Vol.46, (July 1863), pp.17-36.
- Gaddum, F.M., "Walter Ernest Dixon Memorial Lecture: Clinical Pharmacology", Proceedings of the Royal Society of Medicine, Vol.47, No.3, (March 1954), pp.195-204.
- Gauld, A., A History of Hypnotism, Cambridge University Press, (Cambridge), 1992.
- Green, J.P. (ed. & trans.), Interlinear Bible: Hebrew/Greek/English, With Strong's Concordance Numbers Above Each Word, Sovereign Grace Publishers, (Lafayette) 1997.
- Green, S.A., "The Origins of Modern Clinical Research", Clinical Orthopaedics and Related Research, Vol.405, (December 2002), pp.311-319.
- Handfield-Jones, R.P.C., "A Bottle of Medicine from the Doctor", The Lancet, Vol.262, No.6790, (17 October 1953), pp.823-825.
- Hill, R.C. (trans.), St. John Chrysostom: Commentary on the Psalms, Volume Two, Holy Cross Orthodox Press, (Brookline), 1998.
- Jellinek, E. M. "Clinical Tests on Comparative Effectiveness of Analgesic Drugs", Biometrics Bulletin, Vol.2, No.5, (October 1946), pp.87-91.
- Jewson, N.D., "Medical Knowledge and the Patronage System in 18th Century England", Sociology, Vol.8, No.3, (1974), pp.369-385.
- Jewson, N.D., "The Disappearance of the Sick Man from Medical Cosmology, 1770-1870", Sociology, Vol.10, No.2, (1976), pp.225-244.
- Lasagna, L., "The Placebo Effect", The Journal of Allergy and Clinical Immunology, Vol.78, No.1, Pt.2, (July 1986), pp.161-165.
- Lohr, J.M., Olatunji, B.O., Parker, L. & DeMaio, C., "Experimental Analysis of Specific Treatment Factors: Efficacy and Practice Implications", Journal of Clinical Psychology, Vol.61, No.7, (July 2005), pp.819-834.
- Pepper, O.H.P., "A Note on the Placebo", American Journal of Pharmacy, Vol.117, (November 1945), pp.409-412.
- Perlman, L, "Nonspecific, Unintended, and Serendipitous Effects in Psychotherapy", Professional Psychology: Research and Practice, Vol.32, No.3, (June 2001), pp.283–288.
- Platt, R., "Two Essays on the Practice of Medicine", The Lancet, Vol.250, No.6470, (30 August 1947), pp.305-307.
- Rahlfs, A. (ed.), Septuaginta: Volumen II: Libri poetici et prophetici, Deutsche Bibelgesellschaft Stuttgart, (Stuttgart), 1935.
- Shapiro, A.K., "Semantics of the Placebo", Psychiatric Quarterly, Vol.42, No.4, (December 1968), pp.653-695.
- Steele, Dr., "The Charitable Aspects of Medical Relief", Journal of the Royal Statistical Society, Vol.54, No.2, (June 1891), pp.263-310.
- Walach, H., "Placebo and Placebo Effects – A Concise Review", Focus on Alternative and Complementary Therapies, Vol.8, No.2, (June 2003), pp.178-187.
- Wampold, B.E., Minami, T., Tierney, S.C., Baskin, T.W. & Bhati, K.S., "The Placebo is Powerful: Estimating Placebo Effects in Medicine and Psychotherapy from Randomized Clinical Trials", Journal of Clinical Psychology, Vol.61, No.7, (July 2005), pp.835-854.
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