What is a pilot or feasibility study? A review of current practice and editorial policy

Background: In 2004, a review of pilot studies published in seven major medical journals during 2000-01 recommended that the statistical analysis of such studies should be either mainly descriptive or focus on sample size estimation, while results from hypothesis testing must be interpreted with caution. We revisited these journals to see whether the subsequent recommendations have changed the practice of reporting pilot studies. We also conducted a survey to identify the methodological components in registered research studies which are described as 'pilot' or 'feasibility' studies. We extended this survey to grant-awarding bodies and editors of medical journals to discover their policies regarding the function and reporting of pilot studies. Methods: Papers from 2007-08 in seven medical journals were screened to retrieve published pilot studies. Reports of registered and completed studies on the UK Clinical Research Network (UKCRN) Portfolio database were retrieved and scrutinized. Guidance on the conduct and reporting of pilot studies was retrieved from the websites of three grant giving bodies and seven journal editors were canvassed. Results: 54 pilot or feasibility studies published in 2007-8 were found, of which 26 (48%) were pilot studies of interventions and the remainder feasibility studies. The majority incorporated hypothesis-testing (81%), a control arm (69%) and a randomization procedure (62%). Most (81%) pointed towards the need for further research. Only 8 out of 90 pilot studies identified by the earlier review led to subsequent main studies. Twelve studies which were interventional pilot/feasibility studies and which included testing of some component of the research process were identified through the UKCRN Portfolio database. There was no clear distinction in use of the terms 'pilot' and 'feasibility'. Five journal editors replied to our entreaty. In general they were loathe to publish studies described as 'pilot'. Conclusion: Pilot studies are still poorly reported, with inappropriate emphasis on hypothesis-testing. Authors should be aware of the different requirements of pilot studies, feasibility studies and main studies and report them appropriately. Authors should be explicit as to the purpose of a pilot study. The definitions of feasibility and pilot studies vary and we make proposals here to clarify terminology

Historical and modern invasions to Port Phillip Bay, Australia: The most invaded southern embayment?

Port Phillip Bay (PPB) is a large (1900km2), temperate embayment in southern Victoria, Australia. Extensive bay-wide surveys of PPB have occurred between 1803 and 1963. In 1995/96 the Commonwealth Scientific and Industrial Research Organisation (CSIRO) Centre for Research on Introduced Marine Pests (CRIMP) undertook an intensive evaluation of the region with the aims of developing a comprehensive species list of native and introduced fauna and contrasting previous bay-wide assessments with a current field survey in order to detect new incursions and discern alterations to native communities. Two methods were used to meet the aims: a re-evaluation of regional museum collections and published research in PPB to identify and determine the timing of introductions; and field surveys for introduced benthic (infauna, epifauna, and encrusting) organisms conducted by CRIMP between September 1995 and March 1996. The historic component of PPB invasions groups into four periods based on significant shifts in trade activities: exploration/colonization (pre-1839), immigration (1839-1851), Gold Rush (1852-1860), and modern mechanisms (including aquaculture; 1861-present). Invasions within PPB appear to be increasing, possibly due to an increase in modern shipping traffic and an increase in aquaculture (historically associated with incidental introductions); however, the records of extensive biological surveys suggest that this may in part be an artifact of sampling effort. As expected, the majority of introductions are concentrated around the shipping ports of Geelong and Melbourne. Recent incursions into the region include Undaria pinnatifida, Codium fragile ssp. tomentosoides, Asterias amurensis, Schizoporella unicornis, and Pyromaia tuberculata. Port Phillip Bay is presented as one of the most invaded marine ecosystems in the Southern Hemisphere

The relative contribution of vectors to the introduction and translocation of invasive marine species

Whether intentional or not, humans have been responsible for the translocation of invasive marine species. The indicative representations of association suggest that biofouling has been the most prevalent mechanism contributing to such invasions across the globe. Biofouling is one of the oldest mechanisms of human-mediated transport of marine species, beginning with early human movements on small scales and eventually leading to world explorations with the European Expansion from 1500 AD onwards. The most common means of biofouling is marine species attaching themselves to any part of a vessel, or any equipment attached to or onboard the vessel, aquaculture equipment and mooring devices. In contrast, ballast water is a relatively new vector of transport, with the earliest ballast water use recorded in the late 19th century. Ballast water – water (including sediment that has been contained in water) held in tanks and cargo holds of ships to increase stability and manoeuvrability during transit – represents an expansion of transport opportunity to the vast majority of the benthic species associated with biofouling. This project assessed the relative contributions of known marine pest vectors in terms of the introduction and translocation of marine invasive species on a national basis (in Australia) through a review of the National Port Survey Database (NPSD) and on a worldwide basis through a literature review. The information represented by the global dataset and the NPSD provide a useful tool for identification of species associations with modern vectors of transport, and the opportunity to identify likely relationships for future entry. Analysis of the global dataset indicated that more species have life history characteristics associated with biofouling (55 per cent) than any other vector. The second highest association was with ballast water (31 per cent). A similar relative contribution was found in the Australian context through analysis of the NPSD, with biofouling contributing 60 per cent of species association and ballast water 24 per cent

Vectors, shipping and trade

The link between introduction of exotic species into new bioregions and the release of ballast water from shipping is well documented (Smith and Carlton 1975; Carlton 1979; Carlton 1985; Simberloff 1986; Carlton et al. 1995; Ruiz et al. 1997; Shigesada and Kawasaki 1997). Despite the current recognition and acknowledgment of marine introductions via modern vectors, the historic movements of species by vessels may have led to the introduction of species prior to biological surveys

A bay-wide survey for introduced species in Port Phillip Bay, 1995-96

Thirty-three years have passed since the last extensive (benthic and fouling) bay-wide survey of Port Phillip Bay (Port Phillip Bay Environmental Study, Phase One, 1968- 1971) although additional work has been conducted by the Victorian Marine and Freshwater Resources Institute (MAFRI, formerly the Victorian Fisheries Research Institue: VFRI) and the Museum of Victoria (Mo V)

Final Report: CoTS Control Program Independent Review

This Report provides an independent assessment of the CoTS Control Program under the coordination of GBRMPA between 2012/13 – 2018/19, reporting against the Terms of Reference..

Special Invasive Alien Species Issues: Challenges for the marine systems

On a global scale, introduced marine species pose a significant threat to marine environments. Within this paper four challenges to delivery of marine biosecurity outcomes are identified, with a brief discussion on how these challenges are being met within the New Zealand context. Currently within New Zealand, only 3% of the total biosecurity funding is expended on the marine environment. To be effective with such a small component of the total budget, marine biosecurity has directed research into six programmes: 1) risk profiling; 2) compliance monitoring of ballast water exchange; 3) alternative management tools for marine vector threats; 4) baseline information to support border control; 5) surveillance for marine pests; and 6) incursion response options and systems. At present, the marine biosecurity system developed in New Zealand offers a good example of an outcome-oriented system that balances costs and benefits across economic, environmental, social and spiritual values. The short-term costs to establish such a system may be significant however; the long-term benefits far outweigh the initial investment

Marine Platform of Probable Sangamon Age, and Associated Terrace Deposits, Cape Thompson Area, Northwestern Alaska

Reports geomorphic studies, as part of the US Atomic Energy Commission's investigations in this area 1958-1962. A coastal terrace, observed and measured along a 20-mi section crossing Ogotoruk Creek, is described and its origin, age, and morphology discussed. The feature is complex, consisting of a marine platform planed across bedrock, overlying marine and beach deposits, and a depositional upper surface of nonmarine sediments which coincides in area and configuration with the platform, possibly as a result of factors unique to polar areas. The marine platform and gravels record the last high stand of sea level, 28-40 ft above the present, which occurred about 38,000 yr ago. Other evidence in the area indicates still higher seas in earlier times

Biotic and abiotic factors affecting the Tasmanian distribution and density of the introduced New Zealand porcelain crab Petrolisthes elongatus

Petrolisthes elongatus (Milne-Edwards, 1837) was first introduced into southern Tasmania in the late 19th century putatively associated with live-oyster transfers from New Zealand. In the last century P. elongatus populations have expanded, inoculating rocky intertidal zones around Tasmania. We initially identified the scope of P. elongatus introduced range around Tasmania by visiting 57 sites to identify presence. Density of P. elongatus and populations of two native grapsid crab species was assessed at 12 sites around Tasmania to identify any biotic resistance. Abiotic factors including substrate availability and preference, and wave stress, were identified at each of the 57 sites. Our results indicate that P. elongatus has successfully invaded a large proportion of the southern and northern coasts of Tasmania, with a small number of sites on the east and none on the west coast supporting P. elongatus populations. Densities were found to be higher in southern Tasmania compared to the eastern and northern coastlines. Petrolisthes elongatus presence was found to be positively correlated with native grapsid crab presence, however, no statistically significant relationship was found between densities at scales of site or quadrat. Abiotic factors have been identified as the primary drivers of Petrolisthes distribution pattern