The significance of "nonsignificance" in randomized controlled studies: a discussion inspired by a double-blinded study on St. John's Wort (Hypericum perforatum L.) for premenstrual symptoms

Objectives: This study aimed to investigate the efficacy of St. John's wort extract (SJW) as a treatment for premenstrual symptoms. Design: The study was a randomized, double-blinded, placebo-controlled trial, with two parallel treatment groups. After a no-treatment baseline cycle, volunteers were randomized to either SJW or placebo for a further two menstrual cycles. Settings/location: A postal trial conducted from The University of Reading, Berkshire, England. Subjects: One hundred and sixty-nine (169) normally menstruating women who experienced recurrent premenstrual symptoms were recruited onto the study. One hundred and twenty-five (125) completed the protocol and were included in the analysis. Interventions: Six hundred milligrams (600) mg of SJW (standardized to contain 1800 mug of hypericin) or placebo (containing lactose and cellulose). Outcome measure: A menstrual diary was used to assess changes in premenstrual symptoms. The anxiety-related subgroup of symptoms of this instrument was used as the primary outcome measure. Results: After averaging the effects of treatment over both treatment cycles it was found that there was a trend for SJW to be superior to placebo. However, this finding was not statistically significant. Conclusion: The possibility that this nonsignificant finding resulted from insufficient statistical power in the study, rather than a lack of efficacy of SJW, is discussed. Following this discussion the recommendation is made that, in future, similar studies should be powered to detect a minimum clinically relevant difference between treatments.

[Admittatur of John Law (Harvard AB 1804)], 1802 March 1

Published copy of the 1798 College Laws with the admittatur of undergraduate John Law signed by President Joseph Willard on March 1, 1802.

[Admittatur of John Walsh], 1811 February 25

Published copy of the 1807 College Laws with the admittatur of undergraduate John Walsh signed by President John Kirkland on February 25, 1811.

[Admittatur of John Capen], 1836

Printed copy of the 1833 abstract of laws and regulations with the admittatur of undergraduate John Capen signed by President Josiah Quincy on August 30, 1836. The admittatur also includes a certificate of removal from probation signed December 20, 1836.

Captain Mulford's list of writings left in his hands for the publick, ca. 1708

List includes "Our originall deed with the Indians and counterbond" and "Governor Lovelace's confirmation...." One of the listed items, "The testimony of Robert Hudson, Benjamin Smith and John Shaw," is included in HU ALP4671.

An abridgment of what I extracted while an undergraduate at Harvard College, 1766-1769

The bound volume contains excerpts copied by Benjamin Wadsworth from books he read as a student at Harvard in the late 1760s. The volume includes almost no personal commentary on the readings. The excerpts are arranged by year of study for the academic years 1766-1769, beginning when Wadsworth was a sophomore. Each entry begins with a title indicating the book title and author for the passage, and there is an alphabetical index at the end of the volume. Wadsworth selected “extracts” from both religious and secular texts including several histories of England, American histories (with a focus on Puritans), the Bible, and in his senior year, “the Koran of Mohammed.” He also read several books on the art of speech and the art of preaching. There are few science texts included, though the final five-page entry is titled, “What I thought fit to note down from Mr. Winthrop’s experimental Lectures” and contains notes both on the content of Professor John Winthrop’s lectures as well as the types of experiments being performed in class. Wadsworth’s commonplace book offers a window on the state of higher education in the eighteenth century and offers a firsthand account of academic life at Harvard College.

A proof of Jesus Christ's being the ancient promised Messiah: a sermon preached in the Chapel of Harvard College at Cambridge in New England, June 23, 1756

The hand-sewn notebook contains a 24-page manuscript draft of the second Dudleian lecture, delivered by John Barnard on June 23, 1756. The copy includes a small number of edits and struck-out words adopted in the printed version published by J. Draper of Boston in 1756. The sermon begins with the Biblical text Mark 14:61, 62. The covers are no longer with the item.

Lives of the lord chancellors and chief justices of England.

Mode of access: Internet.

Early letters of Sir Henry Campbell-Bannerman to his sister Louisa, 1850-51;

Mode of access: Internet.

A selection from the public and private correspondence of Vice-admiral Lord Collingwood.

Mode of access: Internet.

The lives of the Lord Chancellors and Keepers of the Great Seal of England.

Vol. 8, edited after the author's death, by Mary Scarlett Campbell, 1869.

The speeches of the Right Hon. Lord Erskine : at the bar and in parliament /

Mode of access: Internet.

Speeches of Lord Erskine, while at the bar /

"Memoir [of the author]": v. 1, p. [3]-24.

Report of the committee appointed at a general meeting of the wine trade, held at the commercial sale rooms , Mincing Lane, London, on Tuesday, 26th July, 1842, to take into consideration the measures to be adopted in consequence of the reduction in the duties upon wine, expected to take place, on the conclusion of commercial treaty with Portugal /

Mode of access: Internet.

Reminiscences of many years,

Mode of access: Internet.